I'm using IE 7 for some time and lovin it.

I had believed that IE has done away with the menu. Whatever functionality I needed were available through the Tools and Page split buttons in the toolbar and I always printed using Ctrl+P so I never felt the need of the Menu. However, I just found out some time back from Amit that when you hit the alt button the menu magically appears and then magically disappears!!!

I have no idea what made the IE team come up with such a weird non-discoverable feature! Its so non-standard design. I understand the need of minimal UI and that WinForm enumerates the Alt key as System.Windows.Form.Keys.Menu but would've never figured out the association :)

Update: Windows Explorer also behaves the same way. I have been using Vista for the last 9 months, but couldn't figure that out either. I'm actually feeling foolish for not being able to find out. Oh, hold on, doesn't making users feel foolish make a UI qualify as a bad UI :)