I go back and forth between playing at my house on my xbox, to a friends house on his. Every time I sign in on one or the other I have to recover my gamertag. Is it not possible to use your xbox live account on multiple machines? It gets old having to type my info in every time, am I doing something wrong?
You can't use your xbox live account on multiple machines to prevent people sharing accounts. By forcing you to recover your gamertag every time you move to a different machine it greatly discourages people from sharing accounts.
This is by design, an enormous pain in the butt, but prevents microsoft from having to detect an account logged on two places at once.
Microsoft recommends for people who go back and forth to store your xbox live gamertag on a portable harddrive, this means you don't have to recover you gamertag ever again! By storing it on a USB you can ensure your gaming session is as quick as possible :D
No, you cannot use the gamertag on multiple xboxes at once.
However, you CAN move the Gamertag onto a USB stick and then carry that to your friends house and just plug the USB stick in without having to recover the Gamertag. That would probably be a more elegant solution.