I know of one from a previous project. We had a prompt that said "enter your home address" with JavaScript autocomplete using google location APIs. Unfortunately chrome would try to auto fill this box with a city name (not even the full address) and this auto fill prompt sat on top of the JS drop down.
Well, the web technology is a pile of sh.t and in this case with the textarea you don't put your hands as deep in to is as you'd with the text input. That's how I interact with the web technology.
In our user management portal, whenever tech support opens the Create New User or Reset User Password page Chrome helpfully fills their administrative password into the user's password field.
So in your user management portal, you assign new users or replace your lost passwords with passwords you set, thus you know? Oh my days! Generate it randomly and mail the user, or better, mail them a link to reset/create password page. Otherwise, just make it a plain input field, because if you know it, it's not hidden anyways.
What are those (seriously, I can't think of any off the top of my head).