It happens to me now and then that I misspell my password in a trade. It would be cool if I wouldn't have to re-do the whole trade (or gift) if that happens.
One time I was trading 10 items, all one specific color out of their respective set, misspelled my password and was redirected to an empty page that informed me that my password is wrong. When I hit the "back" button of my browser, all items were removed from the trade and I had to add them all again. This is really tedious.