Check out QuickSilverQuickMailer. It's similar to LaunchBar but I feel that it's easier to use. Here's a screenshot:
If you're a keyboard-junkie like me, it has shortcuts to compose mail and send mail (Compose: Ctrl + ⌥ + ⌘ + m, Send: ⇧ + ⌘ + d) to speed up the mailing process too!
It isn't free, but it's pretty cheap at 99 cents. I don't own it so I haven't tried it out, but I've heard great things about it.
Hope this helps!