I've compiled a little list on tips how to fall asleep fast.
Usually, I fall asleep super fast, but in vacations I hardly have any physical activities (it's unfair: one day I have super much physical activity and a lot of days I have nearly none, repeat) and thus sometimes it takes over an hour to fall asleep (which is too long imho).
Therefore, I wanted to create a little list of things I could do without a lot of physical activity (Except for Exercise!, I know..) to still fall asleep within 30 minutes, preferably within 15.

Tips on falling asleep fast:

Drink warm Milk
I've heard people say normal milk works just as well but my sources say warm milk works a lot better. Either way: Milk! It's nature's way of a sleeping pill.

Exercise!
Physical activities tire the body (dúh?) which allows you to fall asleep fast.

Warning: Drugs >__> - Marijuana and Alcohol.
I quit smoking marijuana but everytime I did, falling asleep took me 30 seconds. Same with being drunk, or close to being drunk (the difference is that Alcohol actually does NOT mess with my dream recall; In fact, my DR is awesome when I was drunk the previous night, and my dreams are SUPER weird. Marijuana is sure to destroy your DR. And another difference is I didnt quit drinking )

Valerian Root
This little plant or whatever it is, is very calming. It's not a sleeping pill (except for "natural" sleeping pills such as warm milk, sleeping pills cause Delta sleep, which causes.. hardly any DR). You can buy these calming pills at your local drugstore (probably), be sure to check the ingredients and see if it says Valerian Root. If it does, then that's the one you should get.

Shower
Some people say a warm shower, some people say a cold shower. Here's my theory:
- Warm showers relax. This causes you to fall asleep faster.
- Cold showers make you cold, and thus it "drains" a lot of energy to keep you warm. It tires you out, physically.

Masturbate / Sex
Another natural sleeping pill + it's physical activity. 'Nuff said.

Alphabet game
The alphabet game. Basically, you find a name (related to something specific, e.g. movies, games, whatever) for every letter in the Alphabet. E.g. for movies:
A: Alien, B: Big Fish, C: Charlie and the choc..., etc. Repeat this a couple of times and you'll fall asleep.

Meditation
Meditation is a very relaxing thing. You can find enough topics on meditation here probably.

Sleep induction preset Bwgen
Download BWGen, write the Sleep Induction preset to a WAV file with the "Play to .wav" option, [convert it to mp3 if neccessary] and put it on your mp3 player/iPod/Zen thingy. Plug in your earphones and listen to it until you fall asleep. The preset is 30 minutes, so you should fall asleep within 30 minutes.

Putting your mind to sleep tutorial

Good luck guys.