A cool feature of Visual Studio 2010 is that any window displayed in the IDE can be pulled out of the IDE as an independent floating window! Just click on the tab of the window and drag it out of the IDE. The window becomes undocked from the IDE and will now behave like an independent window.
I find it useful to use this trick along with the Windows 7 snap feature to have side-by-side code windows for comparison or collaboration. You can also pull a code window into another display in a multiple display setup. You are not limited to code windows, any other window in the IDE: solution explorer, output, call stack, or anything else can be pulled out. To dock back a floating window into the IDE, drag it back into the IDE space using its tab.
This feature is a huge leap over the older tiling and splitting methods of Visual Studio, which were quite onerous.
Reference: How to: Arrange and Dock Windows.