This is really well-implemented...I especially like the transparency feature. Also, it's really responsive; good, since sluggish triggering would have been a deal-breaker for me. My one suggestion is to add a feature where the menu bar doesn't fade away if a menu is open - currently, if I were to open, say, the Edit menu and move my mouse down into the menu, the menu bar dims, leaving just the menu itself at full brightness. Either that, or find a way for just the Edit menu item to remain fully lit. (That would probably be difficult, though.) Great work overall, though!