All,
Was out for a long ride last night, and came upon a guy with a flat, and a busted pump. So, I stopped to help. I use an XLab Saddle Wing to hold the CO2 cartridges and Valve. Got the Valve off, and couldn't get either of the CO2 cartridges off! It was pretty humid, and being all sweaty didn't help, since we couldn't get a grip on the blasted cartridges.

We spent a good 4-5 minutes trying to get a cartridge loose! Finally, got one off, and was able to get him on his way.

When I got back to the truck, I rooted around and found an old towel, ripped one of the ends/seams off which I can wrap around the cartridge to get some dry leverage.

What other tricks are out there? Duct Tape, Sandpaper, etc? Glad I found this out instead of during a Race! :(