Really interesting thread guys....this has been causing me problems for ages. Melatonin is a hormone produced by the brain to initiate sleep and being unlicenced means it is illegal to sell in the UK (also banned in most other countries outside USA). The problem with it (as with other hormone treatments) is that if you use it ...your body starts to reduce its own Melatonin production. Lots of other reported problems with liver damage, heart problems etc.Stay well clear of Melatonin.
I typed "Holiday sleep" into e-bay and got a real outside the box package .... "Jet Lag System" with loads more good stuff! Basically aimed at passengers but the pills work a treat but don't get the side effects headaches / dry mouth etc I get when I used to use Melatonin.
Also had some good fun with the "Crew member special request" postcard.