Tonight I packed the wheel bearings with fresh grease, replacing the preservative stuff that they come filled with. Sorry I didn't get any photos; my hands were too messy to handle the camera.
I've repacked many an aircraft wheel bearing in my time, but I've always done it the low-tech way – globbing in new grease by hand. This time I wanted to try out one of those fancy bearing packer tools. I picked up one of these at Sears, but its plastic housing broke almost immediately. Then I bought one like this, which worked better. It's pretty crudely constructed, but at least it's made of metal. It didn't eliminate the sticky-fingers problem, but using it was somewhat easier than packing bearings by hand. It probably does a more thorough job of getting grease into the bearing, too.
The old-timers' approach is to use Aeroshell #5 for wheel bearings, and #6 for everything else (pivot bushings, etc.). I'm too lazy to keep two different kinds of grease around, so I've always used Aeroshell #22 for everything. (specifications here) It costs a couple bucks more, but one tube is enough to do a half-dozen annuals.