PC Tools Firewall 7.0.0.123
http://www.pctools.com/firewall/
I was going to post that here yesterday after the wannabe admins(they signed up last year and they post a lot, they must be special group) cried about me posting it in the avast pro/free/suite forum and had my post was deleted. Even though most of the complaints about PC Tools Firewall and Avast/Win 7 SP1 conflicts were posted in the avast pro/free/suite forum.
Anyway, the new version of PC Tools Firewall 7.0.0.123 works like a charm with Avast and Win 7 x64 SP1.