Buy.com has the 2GB Kingston Secure Digital Card for only $10. All well and good, you say? It gets better: pay via a new Google Checkout account (simply setup a new Gmail account if you don't have one, or if you have already used Google Checkout through your current Gmail account) and you'll get a $10 off discount on your first purchase, making this free! Plus, shipping is free and there's no sales tax (except CA, MA, MD, TN). The 2GB model is $6.95 more.