I've never had anal sex (not for lack of trying, but my partner is... well-endowed and I epitomize the phrase "Squeal like a pig"), but given my experiences with trying for it, I don't think I'd like it very much. For his sake, I won't give up trying, as long as he only wants to try like... once or twice per year.
I don't really like thongs, because they're uncomfortable to me. My high school best friend had a "wedgie butt" (i.e. her butt was shaped such that any and all underwear/pants invariably wound up in her crack), and she always loved thongs. In her words, "If I'm going to have something in my ass crack, it might as well be a tiny piece of fabric instead of a yard of cotton".
I do not have a wedgie butt, in fact I rarely ever get a wedgie, and thus thongs are uncomfortable to me. *shrug*