Has anyone tried it? It basically changes leveling up by removing how everything else levels to match you. http://www.bncomputing.com/ob/ I DL'd it and started a new character (a hot redheaded thief ) and was more than pleasently surprised. Here's the charts for character/monster levels (they don't gain levels when you do): http://www.bncomputing.com/ob/charts.html It's really brings more of an "I'm UBER" feel because when you gain ranks you'll be more able to own lower ranked creatures/NPC's. It doesn't tell you how to install, but you put the file(s) (I chose to not use the one that makes it so you need to visit a location before you can fast travel) in Oblivion's data directory and then click the data files after starting Ob. Check Adventuerers Ob and uncheck the master file.
Yeah, been running quite a few custom mods for Oblivon, though haven't run any leveling mods. The reason? Reports of it screwing up you're game when you uninstall it and stuff - one poor guy got gangraped by mudcrabs outside the imperial prision =D... Also feel free to check out http://www.elderscrolls.com/forums/ for a whole truck load of good mods... though what i usually do is download a mod I quite like and then boot it up in the CS and edit it to my preferences - you get exactly what you want =)