nothing helps you roll to the bottom of the trails quicker than rum and vodka in large quantities
seriouslly i would normally drink water, its cheap, and if there is a spring near by its free off of Giant ledge in the catskills I found a nice spring near the top ridegeline, no-one had the runs afterwards so I assume spring fed water is still safe, though it has been a few years since my last ascent (Pharoah Mtn in the catskills '02)