Disclaimer: this is my own site, just to be upfront :)
I just finished building a site for the purpose of archiving images of feedsacks. I love feedsacks, and plan to make some quilts with them once I've gathered enough. The downside to making quilts out of feedsacks, though, is that as more and more of the feedsacks get used in quilts, they'll be harder to find. This is an attempt to archive images of the feedsacks so that at the very least, they'll be around digitally.
The other main reason is that it's just fun to look at pictures of them, too :) As time goes by and more images get added, then it may also be a useful resource for feedsack collectors.
If you own any feedsacks, I invite you to upload images of them to the site. You can also upload any images of quilts or other products made from feedsacks.
http://www.feedsackarchive.com