The World's Smallest Dungeon (2005)

The World's Smallest Dungeon is "an adventure for one first-level character." It is a scenario that is SRD compatible and OGL compliant.

From the back of the booklet:

This fully playable adventure, suitable for a first level character of any race or class, is a perfect introduction for new players.

Containing two encounters and a full sized map suitable for use with miniatures, it can be played in less than a half hour.

So, cough up a dollar, grab some dice, and get read to enter...

The booklet does have a listed MSRP of $1.00 and is only 6 pages long.