[link] Shell command - Open folder as Website Project in VS 2005
Visual Studio 2005's Web Application Projects are easy to open from the filesystem by double clicking on the SLN (solution) file. Website Projects don't necessarily* have a SLN file, so I've had to open up Visual Studio and browse for the folder, which is really backwards from how I work.
Bradley posted a cool tip a while ago for how to simplify this. He uses a Visual Studio macro from a shell command (installed by a simple reg file) so I can just right click a folder and select "Open as Visual Studio Website".
*UPDATE - You can use an SLN file, and I guess you get one when you create the project in VS (per Luke's comment). I generally use Web Application Projects and end up with Website Projects which were created by other people and don't come with SLN's.