For those of you who use Visual Studio all day, can I suggest that you install [SonicFileFinder][sff]?
[sff]: http://jens-schaller.de/blog/2008/12/15/295.htm
This lovely little addin by Jens Schaller gives you a way to find files in your current solution with a few keypresses. Invoke it, and you see a dialogue like this;
Type in a fragment of a filename, and you’ll get a filtered list of files matching that fragment. Choose a file, hit ‘return’, and the file opens in the code editor.
Basically, if you know the name of your file, you no longer need to use the Solution Explorer. As codebases get bigger and bigger, this addin gets more valuable as the Solution Explorer gets worse.
Highly recommended, plus it now works with F#, C#, and VB.NET projects.