Project Euler is a series of challenging mathematical/computer programming problems that will require more than just mathematical insights to solve. Although mathematics will help you arrive at elegant and efficient methods, the use of a computer and programming skills will be required to solve most problems.

to play later

looks like an interesting game

seems like this might be a fun game to try out sometime

cute flash game

seems cool

very fun little game

crazy long list of cool (and free) online games

A Massively Multiplayer Online Screensaver (let the gaps in your life dictate when you play; very interesting idea)

Cool looking paper airplane

The ability to easily preview the flake before you're done snipping is great.

Create your own South Park character. Pretty awesome.