I discuss melatonin's effects on sleep & its safety; I segue into the general benefits of sleep and the severely disrupted sleep of the modern Western world, the cost of melatonin use and the benefit (eg. enforcing regular bedtimes), followed by a basic cost-benefit analysis of melatonin concluding that the net profit is large enough to be worth giving it a try barring unusual conditions or very pessimistic safety estimates.
The plus side I've found is there are radically less distractions around at 1am, so I can often get more work done between 11pm and 2am than I can in the whole afternoon. Last night I managed to complete an entire application form for an internship with BP, whereas in the day all I'd managed was half a page of geometry notes.
Possibly even more importantly, mindlessly hitting refresh on facebook is not an acceptable activity at 2am, whereas earlier in the day it is, so if I am awake then, it’s because I'm actually working.
Full essay: http://www.gwern.net/Melatonin