http://www.iconshock.com/icon_sets/twitter-vector-icons-massive-icon-set/
http://www.mobileinc.co.uk/2009/07/free-twitter-icons-for-all/
http://browse.deviantart.com/?qh=§ion=&q=twitter+icons#/d2gwla8
http://browse.deviantart.com/?qh=§ion=&q=twitter+icons#/d2axgxl
http://www.collagist.com/cart/collagist-on-twitter.html#twitter-icons
http://naldzgraphics.net/freebies/free-icons-6-adorable-twitter-icon-pack/
http://playground.ebiene.de/2126/twitter-icons-download/
http://thedesignsuperhero.com/2008/10/free-psds-give-away-high-resolution-twitter-bird-icons/
http://lnx.maurusso.com/?p=1346
http://www.chris-wallace.com/2009/01/02/tweeties-a-free-twitter-icon-set/
http://www.link-creative.com/sprtstwtricons1
http://www.littleboxofideas.com/blog/freebies/tweeta-a-free-twitter-bird-icon-set
http://www.elmastudio.de/freebies/6-coole-twitter-icons-zum-downloaden/
http://www.bijusubhash.com/blog/download-your-free-twitter-bird
http://www.productivedreams.com/free-twitter-bird-icon-set/
http://www.webdesignerdepot.com/2009/07/50-free-and-exclusive-twitter-icons/
http://scarletbits.com/2009/freebie-exclusive-twitter-birds-set/
http://browse.deviantart.com/?qh=§ion=&q=twitter+icons#/d230it0
http://www.blog.spoongraphics.co.uk/freebies/8-free-cute-and-simple-twitter-bird-vector-graphics
http://browse.deviantart.com/?qh=§ion=&q=twitter+icons#/d2azldt
http://www.productivedreams.com/its-twitter-time-free-vector-icon-set/
http://www.smashingmagazine.com/2009/06/24/birdies-cute-free-twitter-icons-for-your-blog/
