Well I have spent some time into modding the cache of this game with the Halo Cache Editor(latest) and it is alot of fun with what you can do. I have found out that you can almost swap anything for something else and it will rarely ever lock-up on you. Some things will do whats called "object overload" when theres too much of one thing it will not load anymore but still. I'm just trying to get that out there that if you are a beginner to modding Halo and you need something to have fun with and EASILY then head over to Xbins on irc
*Efnet, #xbins*
and root around the files in the xbox/apps/ until you find it! If anybody needs just a bit of help then PM me with your problem and I can try to help you with modding the cache...

in some instances, object overload is fun. For example, in the library's cache, you change the biped flood infection forms to biped flood carrier forms, whenever a flood carrier form explodes, it releases flood carrier forms.

I'm kind of suicidal on halo, so this seems fun to me

also, you can change biped cyborg to another biped character, and play as that character.

Unfortunately, if you do this mid-level at a checkpoint, the xbox panics and locks up

Same with if you set it to try and spawn things like skins... it doesn't like that either...

Still, the cache editor is a great and easy program to use, even for noobs like me

EDIT: Spelling