The Frog Prince by Paul Meyerheim, image taken from Wikipedia
First a disclaimer: I am sure this has occurred to someone else, so I did not even bothered googling it. In any case; this is the perfect explanation for the Princess and the frog tale: She did not kiss the frog, she actually licked it; then any slimebag standing close to her looked like Prince Charming.
The frog in question: Bufo alvarius:
People can lick the venom of this toad (right off the toad) to get high or, once the venom is dry, smoke it (the actual psychoactive substance is 5-methoxy-N,N-dimethyl- tryptamine ,or 5-MeO-DMT. This compound can be found in plants as well, such as the trees Anadenanthera peregrine and Virola (a tree related to the nutmeg).
On a side note, the venom of Bufo alvarius has plenty of toxic compounds that can lead to cardiac arrest. Therefore you are better off not doing it. Dance to Modeselektor instead.