One frog that is gaining in popularity as a pet is the Vietnamese Mossy Frog (Theloderma corticale). These frogs (native to north Vietnam at around the 3,000 foot elevation) have among the best camouflage going; they're incredibly difficult to spot in the wild. They've only been in the market for a few years now, but they're turning out to be relatively easy to keep in vivariums. They're classified as 'beginner' frogs on most pet sites. They're even easy to breed, and can be kept in groups (preferred).
This frog is protected by the Vietnamese government (where they're probably under threat because of use in 'traditional medicines'). An interesting note: the eggs are laid on rocks and vegetation just above the water's edge. When the eggs hatch, the tadpoles drop to the water, where they'll spend the next year until they metamorphose into adults.
Also, if you kiss one, you're likely to contract horrible warts--but that danger is offset by the fact that one in ten of them is a cursed prince in disguise. But don't tell my impressionable young daughters that.
Thanks for the frog, Erik.