(swiped from dopaminergic)
*The best summary on my flist is from cmpriest, here.
**Disclaimer: Having had personal experience with cacti, a kitten jumping into a cactus is emphatically NOT FUNNY. It is excessively painful, and can lead to suppurating sores, infection, and in the worst cases, death. I really, really wish people would stop putting it into "funny" reels. Yeah, I get that it's supposed to be funny that the kitten keeps hitting the cactus - but that's because it perceives the cactus as attacking it, because it HURTS. Again, with the not-funny.