Things you CAN'T do during an RPG....
Long list, but well worth it to get all the way through. Just make sure you're not drinking anything as you go. Here's a few of my favorites:
15. Plan B is not automatically twice as much gunpowder as Plan A.
48. The elf is restricted to decaf for the rest of the adventure.
57. In the middle of a black op I cannot ask a guard to validate parking.
68. Bring him back intact includes redundant organs.
92. The name of the weapon shop is not "Bloodbath and Beyond"
99. Not allowed to see if Jedi can parry a shotgun blast with their lightsaber.
111. I did not pick up the garrote skill last week from my grandmother.
122. The paladin's alignment is not Lawful Anal.
134. The King's Guards official name is not "The Royal Order of the Red Shirt"
148. There is no Gnomish Deathgrip, and even if there was, it wouldn't involve tongs.
167. I was not recruited by Star League for any reason.
168. I was also not recruited by 12 dwarves and a wizard to rob a dragon.
176. I cannot make called shots to the plectrum, anvil, stirrup, hammer or Isle of Langerhans.
204. I am not 'too sexy for the elf, too sexy for the elf, so sexy myself.'
213. I am not the patron saint of common sense.
231. I am not allowed to do anything that would make a Sith Lord cry.
249. If a black op requires me to impersonate an employee, I cannot bill the target for overtime.
259. I am not allowed to take any part off of a Starfighter for use in character-to-character combat.
262. I am not allowed to use Smite Evil on any form of supporting architecture, no matter how evil it appears.
264. "Buddy Armor" does not offer any form of cover or protection.
294. Halflings are niether delicious or nutritious, nor do they taste even remotely like chicken
297. Even if she fails her saving throw, it is impossible to get the princess to answer to "Sweetcheeks"
298. And no, a failed saving throw is nowhere near enough to get her to even consider wearing princess Leia's slave outfit.
300. No matter how well you explain the situation, the assault cannon is not concealable in a trenchcoat.
I think I'm going to make a t-shirt of that first one. ;)