I have a link in my signature block so a website that lists many local seed libraries. The ones local to me seem not to have many seeds yet! It's in the back of my mind to bring one of them some seeds next time i have a clean, isolated harvest.
http://www.seedlibrarian.com/
(Checking the link, I see that their locator map is being revised and isn't active right now.
One aspect that I really like is that seeds "borrowed" and then multiplied locally with reasonable isolation are bound to be selected for local conditions and to resist pests and local plant diseases. After being "checked out" and "returned" a few times, genetic drift will have improved them for local conditions. If the seed savers also select for healthy vigorous plants and the best fruits, genetic drift need not lose the special traits that made them a desirable variety.