I have both Halo: Combat Evolved and Halo 2. I don't play Halo 2 because of that annoying Live game account thing that won't take my MSN screenname (which is stupid), but on Halo 1, I do host my own 16 player servers online frequently.
One of my favorite things to do in Halo Full is to run a 16 player rocket server, especially on maps like Chill Out on CTF with bottomless ammo and grenades , especially on blood gulch where you get to blow up blue base . I always like it when you jump while on a hill and a rocket comes by and blow you up with a headshot. lol.