Here are some great stocking stuffers for your Canon 7D user.

Mini HDMI Cable for CANON ($5)
Cheap good quality mini-HDMI to HDMI cable. Enough said.
Heavy Duty Camera Camcorder Hand Strap ($11)
Hand strap for your Canon 7D. Optimize to work without a battery grip.
Canon 2344A001 E1 Hand Strap for Eos Rebel Series ($16)
Great hand grip for the Canon 7D. Requires a battery pack.
Introduction to the Canon 7D, vol. 1 : Basic Controls Training DVD by Blue Crane Digital ($20)
First is a series of two videos on using the Canon 7D.
Opteka LP-E6 2400mAh Ultra High Capacity Li-ion Battery Pack ($20)

The Opteka LP-E6 rechargeable lithium-ion 2400mAh battery is a replacement battery for the Canon 7D as well as other Canon DSLRs. According to the manufacturer, this battery is fully compatible (although I have not used one) and will display the battery levels and will take a charge with the Canon charger unlike other aftermarket batteries available. At less than half the price of the Canon LP-E6, it is worth giving it a try.

Audio Technica ATR-3350 Lavalier Omnidirectional Condenser Microphone ($21)
If you are going to do podcasting or interviews, this little gem sounds great and is a steal! You can plug it directly into the mic input on your Canon 7D or into an externial audio recorder like the Zoom H4n or H1. I recently used this microphone on a project I did for endorsement videos and the result was fantastic.