I've been doing yoga for about six months and I went again last night. I don't do a great deal of exercise so it's a chance for me to get a good workout. The first time I went I thought "Oh this'll be easy, it's just bending and stretching" but at the end of the class I felt like I'd been hit by a truck! Last night wasn't so bad but it was still a workout - my teacher is very sweet but she's a hard taskmaster! My favourite pose is probably kakasana, a.k.a. "the crow".
Other poses I also like are the fish, the camel, the bow, the half moon and the warrior II, images of which can also be found on Ann Pizer's yoga guide. I like yoga because as well as increasing "supplety" and muscle strength, it has the spiritual dimension of a martial art, but without all the bowing and scraping ("Hai, Sensei.") I did jujutsu for a few weeks a while back but they all loved it too much, it was like the evil dojo in The Karate Kid.
Yoga is definitely more up my street!