Another one in the "I might be the last one to figure this out" department. But it's cool, so I want to share it.
I'm a keyboard guy. That's why I love discovering new shortcuts. Today, when working in VS2005, I accidentally hit ctrl-alt-down arrow. So I was surprised when up popped a scrollable list of my open windows. You can even type the first few letters of the filename to navigate the list. I like it better than ctrl-tab when I know the name of the window I want to open, because it doesn't make me visually scan a big unordered list. When I know I want the last window, or the one before that, ctrl-tab still wins.