My favorite tips from Sara Ford's 101 Visual Studio Tips which were all new to me and I tested all of them:

Tip 2: Cycle trough the clipboard stack when pasting text by pressing Ctrl + Shift + V . This allows to past more than just the latest copied text.

Tip 8: Ctrl + , (comma) allows to get a simple type search view (like in Eclipse).

Tip 19+20: Ctrl + Alt + <arrow key> to do block select (like in the command prompt). When starting to type it allows to edit multiple lines.

Tip 37: Ctrl + F3 to search for the currently selected word.

Tip 88: Ctrl + . (dot) opens the small menu e.g. when renamed a method or variable name. No longer trying to catch that one with the mouse cursor :) .

Tip 96: Visualizer for event sender parameter in WPF.

More tips: http://blogs.msdn.com/b/saraford/archive/2010/03/30/speaking-at-devdays-2010-in-the-netherlands-visual-studio-tips.aspx