It’s set up to help you keep track of torches, time spent in the dungeon, etc. in one-turn increments, and it includes notes for 0e, B/X, and 1e. This one’s going straight in my GMing folder, and I’m tempted to laminate it for use with grease pencils/dry-erase markers.
More New Big Dragon goodness
On top of all that, his blog, Save Vs. Dragon, is jam-packed with old-school goodness, including other free resources.