Dungeon Robber
As I’m sure you’ll recall, Dungeons & Dragons has a long history of including dungeon generators for solo adventures. Dungeon Robber is a digital implementation of Gary Gygax’s solo dungeon creation rules. Paul Hughes based it on his poster that recreates the original rules from early D&D.
It’s quite challenging and somewhat arbitrary–very authentic–and has a host of extra features. Including obscure things from the original, such as a rare magic pool that grants wishes. (You’ll want to use your keyboard instead of clicking on the options.)
Play it online here: http://blogofholding.com/dungeonrobber/