B&H Photo is offering rebates on Lexar CompactFlash and SDHC Memory Cards. If you are shooting with a Canon 5D Mark III, Lexar's Professional 1000x UDMA CompactFlash cards do make a big difference in buffer size and continuous shooting times.

Lexar CompactFlash Memory Card Professional 1000x UDMA

Lexar 1000x CompactFlash cards will not improve buffer and shooting times when used on other cameras like the Canon 5D Mark II or Canon 7D, but there are rebates for the 400x UDMA version as well.

Lexar CompactFlash Memory Card Professional 400x UDMA

If your camera supports SDHC Class 10 cards, here is the rebate link:

Lexar SDHC Memory Card Professional Class 10 UHS-I