I was replaying HL earlier today, and it gradually came to my attention that a lot of the mistakes made weren't major, bad just down-right stupid.
This was quite likely down to lack of testing (due to lack of time) by the HL team and maybe pure ignorance... but away... i just wondered what the worst bit of mapping [i]you[/] have found playing HL?
I'll start: a poster placed about 10 units away from the wall. I know its definately not the worst in the game, but its a start!
http://img287.imageshack.us/img287/5439/hlmistake5wv.jpg