Yup, find a friend with an old 360 to use for a couple minutes with your card and a USB flash drive of 2-16GB in hand. If you have no friends with one, drive down to a non-mall GameStop on a slow day at a slow time, like 8pm Wednesday or 11am Tuesday, and ask for a favor where they set a used 360 up for you for a minute. Sweeten the deal by finding a used game for like $20 that you want and offer to buy the $2 replacement plan on it or buy their $15 magazine subscription. An unhelpful register monkey will become more helpful if you make that offer to help their numbers out.
"Hey, I want to buy Assassin's Creed II, but my save is on this memory card. I have a new 360 with no slots for this. Help me out so I can buy the game and continue my save?"