I trust your Holiday shopping has gotten off to a good start!
If you’re a Canon 20D, 30D, 40D or 50D owner, one the best accessories you can buy right off the bat is the BG-E2N Battery Grip shown here. It holds two Canon lithium-ion battery packs and provides twice the normal shooting capacity. During a recent shoot at the Wings Over Houston air show I shot over 4000 exposures using an EF 300mm f/4L IS USM lens and still had power to spare. That’s more than twice the rated “shots per charge” published by Canon.
The BG-E2N battery grip also provides controls and shutter release identical to the camera’s grip when shooting in vertical (portrait) mode. The only exception is that the “AF-ON” button found on the 40D and 50D is missing. Since I shoot in vertical (portrait) mode about half the time, having the vertical grip allows me to shoot from a much more comfortable position whether hand-held or tripod mounted.
The battery grip does add size and weight to your rig but considering the extra battery capacity and vertical controls, it’s a great accessory.