Do you have a dSLR? Or better still, do you have five? Right now you can get five SanDisk Extreme III CompactFlash cards (2GB apiece) for $50.
These high quality CompactFlash cards feature a read/write speed of 20MB/second. And even though they now come in sizes up to 16GB, the MSRP on just one 2GB card is still about $25.