Others have posted this Dungeon Majesty video before, but I was thinking about it the other day, in relation to the "Old School Rocks!" booth planned for the 2011 Gencon Indy. I recognize quite a few Russ Nicholson illustrations, as well as some from Tomb of Horrors.
For all of you who want to support a good cause (namely, promoting the "Old School Rocks!" philosophy) you should check out this OSR t-shirt site. They are selling cool T-shirts with Shawn's Schoolhouse Rock / d20 mashup.