This is a series of mini-dungeons by Roving Band of Misfits. They all have a nice small map with room descriptions and a good introductory premise. They can be run in a two-hour session or less so are good for small side-quests stuck in here and there to a campaign, or short one-shots. They all seem quite realistic and well-thought-out for what they are trying to portray.

I highly recommend the whole series.