As a scuba diver I love the water. On vacation, all I want to do is go diving or grab my mask and snorkel looking for fish, lobster and coral. Every trip, I meet vacationers who profess their love for snorkelling but admit not being able to use the traditional snorkel (breathing from your mouth).
The new Easybreath (link) is a fantastic option for these people. The Easybreath fits over your entire face allowing you to breath normally, has an air intake high above your head (so you don't have to worry about keeping the snorkel straight) and has a one way valve to prevent water from seeping in.
All of this can be had for a low $US55.