I believe Lauri's original blog www.foundclothing.typepad.com is now defunct, but the idea is still relevant: why not consider wearing clothes you find abandoned on the street/sidewalks? Read more about her project here and here.
It's not surprising that some folks cringe at the idea...I always cringe a little myself before picking something up off the ground. But in my case, curiosity usually wins out...
Only a couple things have ever actually made it into my permanent wardrobe--my favorite of all time was an orange Oreda potato shirt. I wore it out to the point where I actually had to throw it away... that was a sad day, mainly because I gained so much value and joy out of a mere found object.
More sidewalk / clothing photos here.