One that comes to mind James is that I trade for a handful accounts - friends, family, etc. - and one day I put a heavy trade on and was supposed to be for just ONE of the accounts. I went into the software to find the one account to place the trade in and I thought I chose the right one...
I put the trade in an account that should never have been that leveraged. The trade was accepted by the broker but the leverage was incredible on that account.
The trade delivered so the account made an incredible profit, but I was managing that thing like a hawk. There was no way I was going to lose money on it. One tick was enough for me in that situation!
That trade sticks out b/c I have never done it since. I don't do many 'account specific trades' now, and this is probably why. I just use OEC's block trading feature and that's it. No over loading the boat here by accident!