Playing 1/2 cash at DTD a few years back now and I made an expensive misclick.
There's a straddle to £4 and quite a few callers, and it comes round to me in the SB. I look at

and I decide to throw in the additional £3. However, instead of throwing in a yellow and a blue chip (£1 and £2), I accidentally throw in a yellow and a black chip (£25) without saying anything. So it obviously goes as a raise. Two people call, the rest fold.
So now there's in the region of £90 in the pot, and I've got the monster that is

.
The flop's not too bad for my hand at all:

It's likely that the callers have overcards to the board and I've got to be ahead most of the time, yeah? So when one leads out for half the pot, I'm thinking I've got to raise here (got about £300 back). Well, anyway the lot goes in, and I'm expecting to see him turn over the nut-flush draw or something. But no, he's holding

. I was ahead pre-flop, but was now needing a snooker. It didn't come, and Mr Bedi was stood behind me watching the hand unfold and all I could hear him saying was "so sick, so sick". I nearly was.