In recent days i've discovered that its possible to trade xbox live content among people who don't have an account like me. it is very possible to take that content and play with other xboxs via syslink...
Unsure if this legal to post but i will if its shut down sorry..
First example the only game i play regularly is Rainbow6:3 they have a new map maybe not too new but a new map none the less to me, called Garage i found this out thru a buddy of mine asking me if i had it, and its a quick simple MOD to the game to make it work flawlessly so now my xbox n my buddies xbox can play syslink games with the same maps..
The content seems to be loaded straight into the E:UDATA[game_number] (ie: E:UDATA55530013) for the game its a matter of getting that content from the xbox live servers and just doing a quick search of where the game places its content i suggest using something like XBSM to find out what exactly the file directory is called but if you back up your games to the hardrive for faster loading like me [god i hate loading times] you just copy the MAP and SYSTEM folder into the game directory and walla! conent gallore so now you you can give your buddies the extras if you want them to play the same maps/cars/whatever have you!
and if you need to back up that content you know where to find it
but in order for any non xbox live machine you take that UDATA folder copy it to the xbox' that needs the information just a straight UDATA[num] to the next xbox machine, and then SYSTEM and MAP directory to the games directory. (ie: F:GamesRB6:3) nothing should be replaced if it is, somethings not right.. but maps load and we have a blast playing them.
Then if it has single player maps that are for the game you just shove those into the the same place, basicly a mirror image of everything the other box has, but i only bother with MP maps cause singleplayer isn't as fun as killing some guys in MP
Hope this helps, hope someone will start releasing some RB6:3 Maps, i love this game!