A server i used to go (urath) had this developed.
Basicly, it was a small mod with a small area containing 2 usable objects. 1 gave you a level, 1 took a level away. Around you were various creatures to test yourself against (barehanded and no equip, mind you) from skellies to elder dragons. A small room let you rest and restore spells as needed.
Could this be done here? Doubtless it would make all the mass-character makers happy, give them something to tinker and fine tune their builds with.
Level Tester Mod
CombatCentral under Arena has been my favorite for this type of thing. You can easily level/delevel to wherever you want. The only thing they restrict is epic dodge (its one of those uber pvp servers where normally you need to roll a 20 to hit) so when i wish to take that, i normally just use epic skill focus: tumble 
-Slave- [GM]
Psycho Banny and all his forms
Psycho Banny and all his forms