This contains a list of Reality Checks. A quote from the FAQ....
Originally posted by Lowercase Society
What is Reality Testing (RT)?
-Reality testing is merely what it sounds, it is testing the reality you are in, and in this case, it would be “Am I dreaming, or am I awake?” This provides a clear way of defining and distinguishing the dream world from the waking world. There are many ways of doing this, but it is good to ask yourself the question as many times as you can in a day. Or you can make a list of things each day to test your reality. For example, everytime you see yourself in the mirror, every time you hear a dog bark, every time you see an attractive person. Hopefully as this becomes a day-to-day task in the waking world, it will become one in the dreaming world. It has been noted that things in the dream world seem very ‘fuzzy’ or words and letters tend to re-arrange themselves in the dream world. If you wear a digital watch (regular ones don’t work as well), look at it once and note the time, look away, and look back at it: if the time has changed or the numbers re-arrange themselves, you are dreaming! You should try this every time you can with reading something, like billboards, a book, or anything similar. You might perform a reality test, upon recognizing a DREAMSIGN.
1. Look at your watch or a clock
This is likely to work, as numbers and letters are normally random in dreams. So, if you look at your watch and it is "12:25" one time and "2:33" the other, you know you are dreaming, and can attempt to become Lucid or something similair.

2. Attempt to Write
When you write, it may not be legible or normal, and the letters may change, as with above. If you notice this, it may be an idea to do another check, or attempt to become Lucid by flying or something similair.

3. Try to find unusual things in the world
These are things to look out for in a dream. If, for example, the sky is green and an alien is attacking you, it is most certainly a dream. Of course, it could be 100 times more subtle than this, as is normal. When you pick up on this, try flying or something similair. This should trigger Lucidity.

4. Find a book, newspaper, magazine, or any other reading material
When you are lucid dreaming, the part of your brain in charge of recognizing numbers and letter is still asleep. If you have problems reading text, or read it once and when you try again it is different, then you are most likely dreaming.

5. Turning the lights on/off
When you are dreaming, one of the things that you are unable to do is adjust the light level of the settings you are in. If you try to turn the light switch on/off and nothing happens then there are 2 possibilities:
a. You are dreaming
b. The light bulb burnt out the light switch doesn't work for some reason.

6. Trying something considered "impossible"
Another method to test whether you are in a dream or not is to try somthing that you know is impossible in the waking life. Commonly used examples of this are: Putting your finger through your palm, crossing over through a mirror, levitating, etc. I suggest you don't try something like flying out your window or such...just to be on the safe side...

7. Memory Check
This is a method where you are "asking" yourself what have happened during the day, or fortunately a dream. Try to think back as far as you can. When you perform this method, you will be aware if you have experienced anything illogical during the day, and you may have blank periods.

8. Mirror Check
Go to a mirror, and look at your self carefully. Ask yourself if you are dreaming. If you are dreaming, it is likely that you will notice something strange in the mirror. For instance, you could have a different hair style from normal, or different clothes. You may also look like you are a completely different person. In this case, you are definately dreaming.

9. Self Observation Test
This is a very flexible reality check. It takes little time, and you could do it almost all the time. Look at your self. If you have, for instance, 7 fingers on one hand, you are dreaming. You could also look at your clothes. If they look strange, you are probably dreaming.

10. Look for a dream sign
Dream signs are common things which appear in your dreams. For example, in some dreams, you may always see a certain person (possibly a dream guide) and the same features (for example, something which does not exist in reality but is always there in your dreams).

11. The Breathing Test
This is a nice all-rounder. Pinch your nose closed and keep breathing. Try not to think about your breathing while doing it, just leave your usual 'automatic' breathing to do its work. Then check if you actually managed to breathe. If you can, you're dreaming.

12. Emotion Analysis
Pay close attention to how you feel. If something causes you to react a certain way - frustration, bliss, laughter, it would be a good time to determine your state. The feelings generated by a dream are the same as in the waking world, so it's certainly something to keep in check.

13. Constant physical awareness
If you're like me, you've been trained to be rushing from point A to point B throughout life. Life is a race and there's no sense of *now*. Learning to control the feeling of now is a great way to pick up on the inconsistencies. I find that learning to consciously acknowledge the little things in life is a great way to regenerate the mind's analytical ability. I find this to be very strong in kids. They will pick up on something insignificant to my mind, and point it out to me, and I will be thinking 'How did you notice that?'
It's that sense of 'now', the feeling that there's not some light waiting at the end of a tunnel, but that the tunnel is filled with light.

In order of appearence
Thanks to:
Lowercase Society for the FAQ excerpt,
Techboy for checks 1, 2 and 3,
Truthbearer for checks 4, 5 and 6,
Human for checks 7, 8 and 9,
Neil for check 10,
Placebo for check 11 and
Awaken for checks 12 and 13.

Other reality checks are discussed throughout the forum. Have a look around and see what you can find!