What's the most "optimal" camera for Scuba Diving?

I’ll be going Scuba Diving in the Summer. I know I have a lot of time to figure this out, but I want to see if you guys have any suggestions (for those who are experienced or have enough information to share).

I’ve done my research on my camera- Nikon d5000, but I don’t think I will sacrifice my $600+ camera for this sake.

I heard about the Flip video camera- has anyone ever tried it?
How was the quality? (No need to further discuss this if not recommended)

I want a camera that is good enough to take a picture of me and the wild life. It should be durable and will not break when I dive with it underwater. Please recommend something under $150.
It does not need to be more than 7mp.

What’s good (in terms of use and quality)?