londrum - 7:15 pm on Feb 6, 2011 (gmt 0)
i wrote a facebook app which is quite handy at getting extra traffic. im not sure that links on facebook really count (i dont think the pages are indexed?) but if you can get someone to share something about your site with other people, then your traffic will shoot up.
i've also written a few wordpress plugins which have links at the bottom. as long as you're open about it, and dont sneak them in, then no one minds. and if the plugin is focused on one subject (your site's subject matter), then it will hopefully only end up on sites with the same subject = more traffic.