Worth sharing, even when it does not fit a familiar shelf.

Good ideas do not always fit a category.

Extra is where Digital Opus keeps simulations, visualizations, interactive experiences, and useful oddities that deserve a public home of their own.

Explore the collection How projects are selected

Collection

Five ways to explore what comes next

Every project is reviewed for quality, purpose, and fit before it appears here.

01

Systems & Decision Labs

Interactive models for exploring systems, decisions, operations, and changing conditions.

6 public projects 02

Learning & Practice

Hands-on experiences for learning, practicing, testing ideas, and building useful skills.

15 public projects 03

Creative & Visual Studios

Visual tools and studios for creating, composing, exploring, and understanding ideas.

5 public projects 04

Playful Curiosities

Polished, unusual, and playful projects made for experimentation and discovery.

5 public projects 05

Practical Utilities

Focused standalone helpers that solve useful everyday problems without unnecessary setup.

10 public projects

Published projects

Ready to explore

Projects stay grouped under the five collections above while receiving a clear page of their own.

01Systems & Decision LabsInteractive models for exploring systems, decisions, operations, and changing conditions.6 projects
01

AD Operations Console

Explore a synthetic Active Directory operations dashboard and preview common account-management commands without connecting to a real directory.

View project details 02

Break-Even Explorer

Adjust costs, price, and volume to see where a simple business model reaches break-even.

View project details 03

Check Digit Lab & Barcode Math Laboratory

Experiment with common check-digit methods and see how identifiers detect simple entry errors.

View project details 04

CPU Scheduling Lab

Compare classic CPU scheduling strategies with visual timelines and calculated waiting and turnaround times.

View project details 05

Decision & Risk Simulator

Compare options under uncertainty by adjusting assumptions, likelihoods, and possible outcomes.

View project details 06

Subnet Sensei

Practise IPv4 subnet calculations and check network, host, mask, and range results.

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02Learning & PracticeHands-on experiences for learning, practicing, testing ideas, and building useful skills.15 projects
01

Battery Pack Configuration Lab

Compare series and parallel battery layouts while watching voltage, capacity, energy, and practical limits change.

View project details 02

Braille Cell Learning Lab

Explore six-dot Braille cells, practise character patterns, and build familiarity through visual and keyboard interaction.

View project details 03

Calendar Mechanics & Leap Year Lab

Explore leap years, month patterns, weekday cycles, and the mechanics behind familiar calendars.

View project details 04

Codon Translation Lab

Step through DNA, RNA, codons, and amino-acid translation with an interactive learning model.

View project details 05

Color Vision Lab

Preview how color relationships can change across common vision differences and compare accessible choices.

View project details 06

JavaScript Logic Trainer

Work through short JavaScript reasoning exercises and check how expressions and control flow behave.

View project details 07

Morse Signal Trainer

Learn and practise International Morse code through visual, text, and timed signal exercises.

View project details 08

Periodic Trends Lab

Compare how atomic properties change across the periodic table with interactive charts and element details.

View project details 09

Precision Measurement & Vernier Caliper Lab

Practise reading rulers and vernier-style instruments while comparing precision and significant figures.

View project details 10

Ray Optics Lab

Move lenses, mirrors, objects, and rays to explore a simplified geometric-optics model.

View project details 11

Resistor Color Code Laboratory

Build and decode resistor band combinations while checking values, tolerances, and multipliers.

View project details 12

Seismic Wave Lab

Explore simplified seismic waves, arrival times, and how changing materials affect propagation.

View project details 13

Semaphore Signal Trainer

Learn flag semaphore positions and practise translating between letters and visual signals.

View project details 14

Shortcut Reflex

Build keyboard-shortcut recall with quick prompts, timed rounds, and immediate answers.

View project details 15

Transformer Lab

Explore an idealized AC transformer model by changing turns, voltage, current, and load assumptions.

View project details
03Creative & Visual StudiosVisual tools and studios for creating, composing, exploring, and understanding ideas.5 projects
01

Celestial Architecture Studio

Compose intricate orbital structures and architectural linework in an interactive visual canvas.

View project details 02

Dreamscape Weather Studio

Blend atmospheric motion, color, and weather-inspired effects into an evolving visual scene.

View project details 03

Firefly Forest

Guide a glowing field of fireflies and watch a small nocturnal ecosystem respond to your pointer.

View project details 04

Noise Field Studio

Shape animated noise fields, particles, and directional motion into responsive generative visuals.

View project details 05

Weather Dashboard

Explore current atmospheric conditions and forecast details in a visual weather dashboard when live data is available.

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04Playful CuriositiesPolished, unusual, and playful projects made for experimentation and discovery.5 projects
01

Arcana Tarot Reading

Draw a reflective tarot spread, explore card meanings, and save a quiet moment for personal interpretation.

View project details 02

Demolition Challenge

Test timing and strategy in a compact destruction-themed browser challenge.

View project details 03

Mystery Box

Open a collection of small randomized surprises, prompts, and playful interactions.

View project details 04

Password Fortress

Explore password length, character choices, and generated passphrases with practical strength feedback.

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Virtual Pet

Care for a small browser pet whose mood and needs respond to feeding, play, rest, and time.

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05Practical UtilitiesFocused standalone helpers that solve useful everyday problems without unnecessary setup.10 projects
01

Client Onboarding Worksheet

Organize discovery notes, project requirements, priorities, and handoff details in one browser-based worksheet.

View project details 02

ContentForge

Turn a short brief into structured content ideas, outlines, and reusable writing prompts.

View project details 03

Epoch Oracle

Translate Unix timestamps into readable dates and move quickly between human and machine time.

View project details 04

File Integrity & Hash Studio

Calculate and compare file hashes locally to check whether two files or saved digests agree.

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GlassFocus Pomodoro

Run a clean Pomodoro timer with focused work, short-break, and long-break sessions.

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Image Triage

Review image batches, inspect likely issues, and organize a first-pass visual triage workflow.

View project details 07

Personal Finance Tracker

Track income, spending, budgets, and account snapshots locally in a personal dashboard.

View project details 08

Service Desk

Explore a self-contained service-desk board for tickets, priorities, status changes, and support workflow.

View project details 09

Stock Tracker

Look up and compare market quote snapshots in an experimental browser dashboard when data is available.

View project details 10

Unit Converter

Convert common measurements across length, mass, temperature, area, volume, speed, and more.

View project details

Curation process

A home for the exceptions, not a dumping ground

  1. Find the right homeWe first check whether the project belongs in an established Digital Opus collection.
  2. Make it understandableThe title, description, preview, controls, and purpose should make sense before anyone opens it.
  3. Publish with careReady projects receive one category and a stable, tested address.

Early proofs of concept stay private. Anything published on Extra should work, explain itself, feel finished enough to use, and be honest about its limitations.

Found something unexpected?Your support helps us maintain these projects and give more unusual ideas a proper home.

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