This deal has ended.
Through tonight, Buy.com has the Logitech Quickcam Fusion 1.3 Megapixel Webcam for $49.95 after a $20 mail-in rebate. This is the best deal I've seen on a webcam with 1280 x 1024 resolution. This is a well-reviewed, high-end webcam that includes a built-in microphone. Shipping is free and there is no sales tax (except CA, MA, MD, TN).