This deal has ended.
Buy.com has the large and fast 2gb Kingston 50x Elite Pro Compact Flash Card for only $19.95 after an $18 mail-in rebate valid through 3/3. Speed affects the startup time of the camera, time between pictures and file transfer time. Plus, shipping is free and there is no sales tax (except CA, MA, MD, TN). This is the best deal I've seen for this or similar.