Pretty sure I've mentioned this before...
Years ago I worked for a little company, based in an old sawmill. We decided to build a partition wall to turn our large and pointless reception area into a small reception and an office. We bought a door from B&Q, measured it up and built a studwork partition, onto which we would put boards, and paint.
To check the door fitted into the gap we'd left, we (rather predictably) put it where it was going to go. Stepping through a gap in the studwork, I checked that everything looked okay.

"Yep, that's all fine" I confirmed to my colleague, then went to rejoin him on the other side of the wall.

By going through the door.

My feet both got as far as the bottom of the door; my hand was still holding the door handle and I fell forwards with the door, unable to do anything to break my fall.

Approximately eight days later I managed to stop giggling.
(Professor Kenny Martin Hmm? What?, Sat 23 Mar 2013, 13:57, 1 reply)

Encapsulating..
the best and worst about a cock up like that, the inability to do anything after for laughing.
(Beer Elf Thought this was like a campfire, anyhow, on, Sat 23 Mar 2013, 20:54, closed)