I heard those things could hitch a ride on the space shuttle, on the outside There's some speculation that they could have originated some place other than earth. Or at the very least, they'd be able to survive on other planets if they hitched a ride on spacecraft
I've thought about this question in the past. -- I'd want to be a Tabby Cat that lives in a quiet neighborhood, has a cat door, get's great Veterinary Care, gets great grooming, has a clean little box, and is owned by a woman in her 30's that Loves me.
I would be an owl. I'm nocturnal so it would be an easy transition, and I'd like to be able to fly around.
African vulture. Easy living I imagine, because to them, dinner is always served. Fresh carcasses right there, just ripe for the taking. Tasty, protein-rich meat that somebody else killed for you, so I wouldn't even hafta work for it all that much. And I could fly and be above all the world's bullshit, and there'd be no shortage of great weather. Sheer bliss.