Get 5 black soul gems and 5 pieces of armor (helmet, curiass, greaves, gauntlets, boots). Soul trap 5 Humans (arena battles work well for this) Go to the mages guild and enchant the the armor with Chameleon spell. You will end up with 20% chameleon on each piece for a total of 100%. No enemy will attack you even after you hit them, they will walk around stand there and just keep taking hits. Makes the game very boring but it works.
(supplied by: devlon)