So, before I would play the game full screen, but I would use Alt+Tab to switch between windows if I need or want to do something during moments of downtime.
And then, one day without paying attention, I pressed Alt-enter on accident.
Except for one time, now when I play on full screen I don't get the standard Alt-Tab menu. I just get a black screen for 10-25 seconds while it minimizes, and bringing the game back up requires about that much time as well.
Not really sure how I'd go about making things "right" and have alt-tab not minimize Hawken. And playing in windowed is freaking annoying.