Here are some interactive pages that I have written with javaScript. Click on the names to view the respective pages. I do not guarantee the results of the different calculations on the pages, but I have done my best to make sure everything is correct.
Cool Things
Binary Clock A funny alternative to your normal clock.
Backwards Makes your text start at the end. Useful for confusing your friends.
Roman Clock A digital clock with roman numerals, a must see!
Reaction Time A tool to measure your visual reaction time.
Games
Hanoi Towers The classic game. Solve it yourself or let your computer do it.
NetMines Game Locate those mines and save the world by logic thinking or risk anihilation.
The game of Netris A familiar and very addictive game.
Miscellaneous
Numerals to Letters Converts numbers into numerals for 9 languages including roman numerals.
Readability Index Calculate the readability index of a text just by pasting it.
Molarmass (Chemistry) Calculates the molar mass of a molecule.
Peptide Analyzer (Biotech) Gives structural information, molar mass, and hydrophaticity plot.
Morse Coder Translates text to morse code and morse code to text.
Math related
Primes Check a number for primality or finds all the primes under a given number.
Triangle Calculate missing sides or angles in a triangle using trigonometry.
Fraction Approximator Find the fraction for a decimal number.
Quadratics Find roots and toppoint of a quadratic.
Linear functions Regression of linear functions and their ortogonal functions.
Temperature Converter Converts between Kelvin, Farenheit and Celcius.
Angle Converter Converts to different angle measurement units.
Notation Systems Converts from the decimal number system to others.