Okay, so maybe it wasn't a fair test - I was super tired (insomnia/disrupted sleeping pattern for over a week), and the weather broke last night with a huge thunderstorm - but:
I took melatonin before bed and slept like the dead. In fact, I also slept much of the day away. If it happens again tonight, I'm calling it a success.
The dose is 3mg, and includes B6. I took it about half an hour before bed, and though I can't tell you how long it took me to fall asleep, i can tell you that it happened pretty quickly.