I've been working on trying to keep the GM's side of the table a bit less cluttered these days. I love the digest sized books or smaller for quick look-up reference. I needed a quick guide for monster stats so I didn't have to flip through books for AC, Experience, Damage, etc.
I've put together The Warlock's Digest of Dungeon Dwelling Denizens, a no frills old school monster statistical reference in digest format. It lists the stats only for all the monsters published in the Swords & Wizardry Core rules with a couple others monsters that I've used in my campaign thrown in. It sports ascending and descending armor class so it should be helpful in most old school style games.
It's a free download so have at it!