I'm not the guy to go around snooping in dungeons, but this was a rare case. Alone, with tools the equivelant of stone, I randomly find this. It had a CD in it, which added to the score factor! And, then, I get griefed somehow. Hey, come and mine the ground below me, if you can find it.
Let's see...A CD, some gunpowder, wheat and redstone. Not bad for one dungeon. (and there was only one spider when I got there, too.)