Ultralight freaks unite! We have nothing to lose but the weight of redundant gear! :-)
NOTE: We're all different, we all have different equipment/techniques that work for us. The links below offer a range of options and approaches. What works for me may not work for you, and what works for them may not either. But between all of us you're bound to find something useful. The important thing is to find out what works for you! Not Ultralight Joe's Way, not Bob's Way, not Ray's Way. Your Way!
Ray Jardine's Adventure Page - Ray literally wrote the book that inspired many ultralight hikers. I've never read it, but I'll bet many of the ultralight techniques I've heard over the years took form in those pages. He tends to be rather opinionated about things however. Always follow your own head and heart. There is no "One True Way", there is only what works for each of us and our specific needs, goals, and desires. The oldest nugget of trail wisdom is "Hike Your Own Hike". Everything you run across should be nothing more than a starting point for you to put you own personal spin on gear and techniques that work for you.
The Lightweight Backpacker - Extremely thorough, very well done. A great resource with a professional look and good content.
Onestep's Ultralight Backpacking Resource. Some nifty info, links, forum and a chat hour every Tuesday night. Meet up with your virtual friends in realtime!
Great Lakes Lightweight Backpacking. The usual you'd expect to find, along with winter- and tarp camping tips. And of course a little info re: the Great Lakes region. :-)
Bear's Centerwalk. John has put together a really nice site. Ultralight travel as well as general backwoods skills, gallery, tracking, and more.
Adventure Alan's Ultralight Backpacking. Nice site, lots of info, great trip reports! With plenty of photos to help you soothe the pain of being stuck at your desk. Summer 7.6 lb gear list and more.
Jason's Ultralight Backpacking, by old friend and fellow ultralighter Jason (aka "Chilli Bistro") has some great pics (rock climbing too - Jas we've gotta hit JTree again soon!), gear list, etc. Lots more to follow. Hopefully with me tagging along. :-)