No doubt that this topic has been exhausted, but why is a sealed bottle of water from home prohibited, yet sharpened scissors are allowed, provided they are four inches or less in length? (Source)
It's as if whoever makes these regulations has never flown in a plane and has no clue what it is to be a passenger (ie, humans need (in this case) to drink water and shouldn't be limited to [no doubt outrageously overpriced] water bought "after security screening"). So many of these rules seem to have almost nothing to do with safety.
Edit: I edited the title to lowercase the 'a' in 'and' but apparently there is a script that makes this impossible. Smart. (Not.)
[Edited 2006-09-27 21:19:01]