I hate it when a mouse click doesn't register. I hate it more when the mouse grabs something like a window or the video time bar on YT for no other fucking reason than to be obnoxious. :/
I think my ever-faithful trackball is slowly losing its mind. Sometimes, it doesn't register a click, and other times, it'll register a single click as a double-click, which, as you can imagine, leads to the occasional bout of OCD-fueled frustration.
What really sucks, though, is I have YET to find a replacement online that's the same style as mine. That is, to say, with the ball in the front middle, with buttons on both sides, like this...
Actually, that's the exact trackball I have, except its weathered from use. All the other kinds I see, the ones I get all the time when I search Newegg, have the ball way off to the fucking side or some other moronic bullshit. Not only are those things, to me, incredibly ugly and unintuitive, they also take up a damn sight more space.