I've been using Blogger's Scribe template since I started this thing last year. While I liked the parchmenty feel of the colors, I had two bones to pick with it: ordered lists were always displayed as unordered, and the horizontal rule didn't work, which led me to do stuff like centering three asterisks to set off quotes.
So I've been messing about with other templates. Simple II was too simple--I like having the recent posts and archived months displayed. I'm really liking Mr. Moto, by the esteemed Zeldman. I'm liking it a lot so far--and I see that my numbered lists are now numbered and my horizontal lines appear. Thank you, Zeldman.
Addendum
The Quick Online Tips site (powered by Blogger) has a good post on free Blogger tools. And he's pointed to other Blogger templates here.