Here is the latest in my link-listing series. Also check out my ASP.NET Tips, Tricks and Tutorials page for links to popular articles I've done myself in the past.
Visual Studio Programmer Themes Gallery: Visual Studio enables you to customize the color settings of the text editor and IDE, as well as to export and import the settings (use the Tools->Import and Export Settings menu to do this). Scott Hanselman has a great post that provides previews of a bunch of cool pre-built themes that people have published that you can download and use for free.
Using the Expression Tree Visualizer: Charlie Calvert has a nice post that talks about one of the very useful debugging tools in the LINQ samples package provided with VS 2008. It enables you to easily visualize expression tree variables within the debugger - which can be incredibly useful when you are trying to write your own custom LINQ provider (like the ones above). To learn more about Expression Trees and some of the underlying concepts that make LINQ possible, also check out Charlie's earlier post on them here.
Hope this helps,