I was out enjoying my bog garden tonight, and noticed a little frog peeking out of one of my pitcher plants -- this one is Sarracenia "Dana's Delight", a named cultivar. So I got out my camera and took a few photos. There were actually three little frogs -- each about 1.5 cm in length -- inside the trumpet. They were fully capable of scaling the waxy inside walls.
Seems like a nicely symbiotic relationship -- the plant provided shelter from predators and the hot sun, and attracted insects for the frogs to eat. The frogs, in turn excreted nitogen-rich waste which is a lot easier for the plants to absorb.