Appears On
Enter your retail price, wholesale cost, ad spend, and units sold to instantly calculate campaign profit — or find your break-even point automatically.
A 100-record address book with entry, change, list, and name/city search modes — all packed into under 150 lines of BASIC.
A compact circle-area calculator using the built-in PI constant, hardwired to radius 5 — then it lists its own source code after saving.
A complete three-account personal finance ledger from 1983 that validates transactions, sorts by date, compounds monthly interest, and prints formatted statements.
A fully playable Blackjack game with graphically rendered playing cards built from block graphics, ace logic, five-card trick bonuses, and a wagering system.
Crack a time-travel mystery by decoding memory zones — this adventure hides its clues in a clever delta-encoded string table with a scrolling marquee display.
A car loan payment calculator using the amortisation formula — spot the typo that breaks the interest rate conversion before it runs.
Enter six digits one at a time and this program calculates a weighted checksum digit using alternating 1-2 weights and iterative digit reduction.
A short circle circumference calculator that uses the built-in PI constant and a fixed 35-foot diameter — with a few intriguing unreachable lines at the end.
A coin-flip decision maker that answers YES or NO to any question — but there's a hidden gap where it stays silent.
This tongue-in-cheek management consultant simulator picks one of ten corporate non-answers at random — press any key to get your next decision.
Enter a Fahrenheit range and step size, and this temperature converter prints a tidy three-column F/C/K table with randomly-generated block-graphic borders.
A pixel-drawing program with cursor keys 5–8 and toggleable draw/erase modes, showing boundary clamping and mode-switching techniques in under 20 lines.
A prime factorisation tool using trial division with an odd-number skip and square-root cutoff — see how the flag variable catches lone primes.
A full flat-file database manager with add, edit, delete, search, sort, and tape-save — all driven by a single computed GOSUB dispatch.
A straightforward payroll calculator that correctly handles overtime at time-and-a-half for any hours worked beyond a standard 40-hour week.
Choose two flavours and watch this program build a two-scoop ice cream cone pixel by pixel using block graphic characters and clever circular approximation.
A compact loan amortisation calculator that applies the classic annuity formula, converts annual interest to monthly rate, and loops for repeated calculations with a keypress pause.
A complete ZX81 machine code toolkit offering hex entry, memory listing, block move/copy, RAMTOP adjustment, byte search, and RAND USR execution from a single menu-driven program.
Enter up to eight quarters of marketing figures and watch this program draw a comparative horizontal bar chart — capped at 22 units each — using block graphics.
Enter ad cost and circulation for two media and instantly compare their Cost Per Mille to find the better advertising buy.
A practical monthly car expense tracker that computes MPG, fuel costs, IRS mileage deductions, and optional additive costs, then prints a full report via LPRINT.
A compact rolling-window statistics tool that continuously tracks mean and population standard deviation across a user-defined number of inputs.
Enter any number and watch its multiples highlighted among 0–99, while non-multiples are masked with block graphic characters in a clever visual trick.
A compact multiplication table printer that quizzes you on any times table up to ×10, looping until you type "NO" to quit.
A bidirectional base-2/base-10 converter that uses logarithms to find the highest bit and processes binary strings character by character.
A number-guessing trick that walks the player through doubling, adding, and subtracting, then seemingly reads their mind to reveal the original number.
A two-player number-guessing trick that secretly reverses each player's arithmetic steps to reveal their original numbers — can you spot the algebra?
A complete quiz-authoring toolkit that packs questions, answers, choices, and explanations into a single string using pointer arrays — and even pre-calculates available memory before you begin.
Fifty random bars plotted pixel by pixel, then a calculated mean line drawn across them — a compact statistics visualiser in under 130 lines of BASIC.
A real estate database storing 60 property records with a machine code–driven scrolling spreadsheet view, all packed into a single BASIC program.
Pull the trigger ten times in this Russian Roulette simulator where a single RND value determines your fate — and one subtle probability gap might just save your life.
A random-data dual-series bar chart using block graphics to show overlapping sales figures for nuts and bolts across five simulated years.
A commission calculator that mirrors every result to a printer in inverse video, with a tight input loop and some intriguing unreachable code at the end.
A month-by-month compound savings calculator that tracks balance, monthly interest, and cumulative interest with careful two-decimal rounding throughout.
Enter a starting balance, interest rate, and time horizon to watch compound interest build year by year in this simple savings projection tool.
A random substitution cipher generator that assigns each letter a unique three-digit code, using collision detection to guarantee no duplicates appear in the table.
A week's worth of random four-digit security codes, one per day, generated and sent straight to the printer with a neat rejection-sampling trick.
Enter two brand names, quantities, and prices, and this vintage shopping helper instantly calculates which product gives you the best value per unit.
Race to decelerate a starship to docking speed by correctly naming planets in this narrative quiz game that pits your solar system knowledge against a dual-speed countdown.
Guide your Earth ship against waves of encroaching aliens in this 1983 arcade shooter that uses clever string tricks to animate laser fire across the screen.
A 15-question weighted stock evaluation quiz that tallies P/E ratios, dividends, and market conditions to decide whether a share is worth buying.
Spin three random graphic characters and match them to win virtual cash in this vintage slot-machine simulator with a surprisingly clever character-selection algorithm.
A two-way temperature converter with a subtle but consequential arithmetic bug hiding in one of its conversion subroutines — can you spot it?
A BASIC raffle drawer picks random winners from a numbered ticket range — but a subtle variable bug means the range calculation may never work as intended.
A no-frills trip-time calculator that divides hardcoded distance by speed — edit two lines and run to get your answer in hours.
A handy retail utility that takes item name, quantity, and total price, then instantly calculates and displays the cost per unit.
Enter any word and watch it displayed four ways — downward, upward, forward, and backward — in a neat BASIC string-manipulation demo.
A surprisingly capable word processor that stores over 5,000 characters, offers paged navigation, search, inline editing, and printer output — all in pure BASIC.
A full-featured, ten-page word processor with two editing modes, cut-and-paste buffers, text justification, and printer output — all in pure BASIC.
