The best ways i have found to ensure my code stays mine:
1. Dont give it out. i know this isnt possible if its a group project, but as a rule no one elce gets any significant parts of my code.
2. Copywright it. just make sure you put comments with © YourName Thedate.
example: © ZeroAlpha 2003
3. Easter eggs! it may sound funny, but code a few in. then if your code comes into question, simply point them out. the cheaters probably wont have gone through your code looking for well hidden supprises.
[ 12-10-2003, 11:10 PM: Message edited by: Zero Alpha ]