I have entered the One Page Dungeon Contest - http://campaignwiki.org/wiki/DungeonMaps/One_Page_Dungeon_Contest_2013
You can download a copy from here: The Witch's Hut.
It's just a quick encounter that I thought up, but I actually quite like it... so I will be using it on my own players this weekend.
One thing I did notice, if you make something like this completely system agnostic it becomes really easy. The hard parts are in the details.
Had a lot of people download the Underworld rules (which are free) but only two buyers so far. Wasn't really expecting a lot with spending some effort on advertising. No feedback or comments tho either.