1. Move Now Think Later: http://www.movenowthinklater.com/
A bunch of checkers pieces moving fast.
2. Language is a Virus: http://www.languageisavirus.com/
This website will give you ideas of what you can write about and you even can play some writing games.
3. City Creator: http://www.citycreator.com/build.city?city=1
It's like building your own Habbo city.
4. Storyline Creator: http://storylinecreator.checkmates.de/creatorDemo/index.html
Input your characters and the actions they take to visually map the plot of your story.
5. Dendrite: http://dendritestories.co.nz/
It lets you read stories by other users or you can write your own.
6. Book Seer: http://bookseer.com/
Put in the books you love, and it'll recommend similar ones you might like.
7. Reshaping Excellence: http://www.sennheiser-reshapingexcellence.com/en
It lets you create an sculpture out of sound, and then add it to a larger sound monument.
8. HTML5 Drum Kit:
http://www.randomthink.net/labs/html5drums/#00000000000000000000000000000000000000000000000000000000000000001100011010000110101010011110100110101001101010011010100110100110110001101010000100000000000000010000000000001110000000000000000001010101010101011010101010101010%7C110
It lets you create your own beat out of squares.
9. DOT Music Player: http://hakim.se/experiments/html5/keylight/03/#
If you don't like squares you can use these dots to make music, kind of pretty.
10. Morning Mood: http://data-bites.com/piano/
Rendition of Morning Mood that you can play by just pressing random keys.
11. Keep Me Out: http://keepmeout.com/en/
A site that blocks any website of your choice by the amount of time you choose so you can be more productive.
12. Birthday Star: http://freeant.net/birthdaystar/
Here you input your birthdate or just a year, and it'll show you stars that are at those many lightyears away so you can see the light of the time of your birth coming from a star.