Dump games on it if you have the NXE dashboard. I just took gears 2 off my HD and put tales of vesperia on it. When you put games on the HD, it doesn't require you to use the 360's drive/laser and the system runs a bit cooler and you can barely hear it.
Also, even though it's "20 gig" you can only use just under 14 of it.
^ oh yeah? damn i think i need to do that..because sometimes gears of war is on some 'this disc is unreadable' bullshit and that sounds like it might help..good looking on the info..