I recently purchased a Canon underwater camera. It's good to 30 feet so you don't have to worry about how deep you go when snorkeling (most are to 10')
It can also be dropped from 5 feet (I've already done that) and is good to some incredibly low temperature so if you ski it'll work on the mountain. So far, I love it. Light is an issue and it's flash isn't as good as the scuba camera I once had, but for hauling around on the boat, snorkeling, etc. it works great. I studied a lot of reviews and the best "bullet proof" cameras were the olympus and the canon. Both are in the low US$300 range. I've ruined enough cameras it made sense to me.