Here's an interesting camera for summer activities: the Olympus Stylus 720 SW. This very pocketable point and shoot is immerse-able in water as deep as 10' for as long as an hour. And it can take a licking too -- up to a 5' drop -- and still keep taking pictures. On top of that, it's kind of cute.
If you're looking for a tough little camera that can survive the rigors of summer activities, you might want to take a closer look. The 720 SW has a 7.1 MP sensor, 2.5" LCD monitor, 3X optical zoom, 28 preset shooting modes, uses xD-Picture Card, has 19.1 MB of internal memory that lets you shoot even when your media card is full, and comes with a Li-Ion rechargeable battery and charger.
The 720 SW has ISO settings for 64, 100, 200, 400, 800, and 1600, but I don't recommend going above 400 except when absolutely necessary to get the shot. You can capture video and sound with the QuickTime movie mode at a maximum quality of 640x480 at 15 fps.
The Olympus Stylus 720 SW is available online at Amazon for about $360.