Jigsaw Puzzle Game

Has anyone done a jigsaw puzzle game, like www.jigzone.com?
My wife would like me to code something similar and i am looking for tips and tricks. I will formulate a plan and post it in a worklog over the weekend and i would appreciate feedback on what other people have found to be issues or difficulties.

Cheers
Glenn

There was one a while ago called Jigjag Gold. Was really good, too.

I have added a worklog here: http://www.blitzbasic.com/logs/userlog.php?user=9233&log=1489
(not sure how to create the links like other people do yet).

I wouldn't mind some feedback on if it is as simple as i am describing.

Cheers
Glenn