I know that this idea has been done several times before, but I decided to do my own list. I know it's really short, I'll add more later.
1. Never, under any circumstances, mess with Dean’s precious Impala.
2. Don’t piss off the nerd angels.
3. Giant teddy bears are extremely depressed and suicidal.
4. Myspace is a porn site.
5. Sacrificing is classier than killing.
6. Unicorns ride on silver moonbeams and shoot rainbows out of their ass.
7. When an angel loses their faith in God, the appropriate response is to go on a bender.
8. Movie monster names can double as verbs.
9. M&M’s are perfectly acceptable wilderness provisions.
10. Don’t make deals with red-eyed people.
11. Angels do not understand cell phones, but its adorable when they try.
12. The light at the end of the tunnel is Hell fire.
13. Bigfoot is a hoax.
14. Clowns are evil and eat people.
15. If you’re a Winchester, dying isn’t always permanent.
16. Family is everything, and doesn’t always end with blood.
17. Demons are perfectly logical. It’s humans who are crazy.
18. When your brother goes crazy and tries to kill you, make sure you give him an unloaded gun.
19. People can be in two places at the same time.
20. Driver picks the music, shotgun shuts his cakehole.
21. If you are a bully, there’s a good chance Lou Ferrigno will burst through your front door.
22. Sam and Dean are idjits.
23. If Dean hasn’t said a variation of the word bitch in over an hour, he’s either possessed or a shape shifter.
24. If you say the word Djinn too much, people will think you’ve been drinking.
25. When aliens are slow dancing and alligators are in the sewer, it’s time to call Bobby.
26. Demon blood is better than Olvaltine.
27. The apple pie is freakin' worth it.
28. People actually do have neighbors named Mr. Rogers.
29. Fairytales are real, and are out to kill you.
30. No matter how bad things get, they can always get worse.
31. When someone calls you a bitch, the appropriate response is jerk.
32. Zeppelin rules!
33. Time warps qualify as "dingo ate my baby" crazy.
34. Bert and Ernie are gay.
35. If it's the middle of Basic Instinct, you can still bang Sharon Stone.
36. The best hangover remedy is a greasy pork sandwich served up in a dirty ashtray.
37. God is not on any flatbread.