Book of Souls for my rogue's epic. Zoned in to Plane of Hate all alone and there were an amazing number of liches around. Had to sneak up on the rail over the bridge to get passed some liches, run around through the streets and ducking in a couple of corners to avoid a wandering lich. Then into the hall where the book was lying on a table, fortunately not next to a lich.
Grabbed my book , ran out the doors and up the big stairs to the Maestro's place 'Rocky' style, shouted 'I'm the best rogue in Norrath!' and promptly gated out.
Granted, it only took maybe 5 or 10 minutes and was super simple, but it was the first and only time I've felt like I was playing a real thief. Picking the pockets of dark elf rogue guildmaster probably would have been nervewracking and awesome as well, except I got it on the first try so, not so scary.