[Wlug] SPF

Hi, Are any of you admins out there running SPF, or something similar? http://www.openspf.org/ How well does it work for you? Today I started getting a large number of "undeliverable" responses due to spammers forging my email address in the From: address. Wondering if SPF is worth the trouble to set up. I'm using postfix, btw. Thanks, -Jamie