OK just to let you nostalgic players like me that are waiting for Halo Anniversary be even more stoked, I'll let you in on something awesome that not that many people know. [ Register or Signin to view external links. ]
So far I've been modding the crap out of single player with homing rockets and other goodies. Just thought I should give a heads up that Halo is very much exploitable on a retail 360.
Summary of video in simple terms:
Save and quit on any single or multiplayer map.
Turn off Xbox and remove 20+GB HDD. Then connect it to PC using transfer cable.
Open up Modio and look in Partion 0 for Xbox 0. (For me it was in Xbox 2)
You will see Cache000 and up. Those are the maps. The first two (The ones that are about 278 megabytes) are single player maps. Extract those onto your desktop or wherever and open them up with Halo Hacker Tools v5.
Mod it! Swap projectiles, weapons, just about anything and even add homing! But be warned, as anything you add or swap will effect the AI so don't go making plasma pistols shoot rockets unless you want them to blow you up!
Last step, close file in Halo Hacker Tools and inject the file you just modded onto your HDD. It'll ask if you want to overwrite. Say yes. Plug it back in and enjoy!
Edit: Here's Assault on the Control Room modded by yours truly. Although I think you may have to unlock that map before you can play it first.
[ Register or Signin to view external links. ] (My Modded Assault on the Control Room)
[ Register or Signin to view external links. ] (Halo Hacker Tool's v5)
[ Register or Signin to view external links. ] (Modio)
P.S I am BULLDOG266 from game-tuts so this maybe a copy & paste but just spreading the word for nostalgic players like me!