There is a new free vector resource on the Web and it's a bit different from everything else you've seen. Public domain vectors is a website that offers royalty free vector images and graphics released under Public domain license. That means users can use, edit, distribute and modify vectors for unlimited commercial purposes without asking for permission. Most of the vector graphics on this site is original, created by people from publicdomainvectors.org and is of quite decent quality, considering the ultimate free commercial license.
Searching on the website is easy, you can either use search engine or tags to locate free vectors. Vector images are also categorized in several categories like Animals, Backgrounds, People etc, for easier searching.
If you want to contribute and upload your own vectors released into public domain, just register, create account and start uploading.
All in all, this kind of resource will definitely be very useful for designers hungry for free vectors with unlimited commercial license.