Simulator

If you like to play God, the British interactive design company Soda Creative Technologies Ltd. can help you work out your controlling--er, creative--urges. Its Sodaconstructor game gives you a wire-frame, jellyfish-like creature that marches jauntily back and forth across your computer screen; it's up to you to alter physique or physics (by turning gravity on or off, for example). Don't be surprised if you end up growing so proud of your new pet that you want to trot it out like a show poodle in the Sodazoo.

http://sodaplay.com/constructor/index.htm