Buy.com selling a 1 GB USB key for $50. Using Google Checkout (which I guess just rolled out) gets you a $20 discount and since you’ve sold your soul to Google, you’re lighter in the trunk. There’s also a $20 and $10 mail-in rebate (processed by Coresco/rebate411.com, which seems competant from my quick research). Free shipping means that post rebates the drive costs about $1 for stamps, envelopes, and photocopies.
FWIW I paid 24 for one from bestbuy out the door and walked in and picked it up.