Even if you have 8 logical cores in your pc, the build system in Visual Studio 2010 still uses only a single core to build your solution.
If you work with small projects that isn't such a problem. If you however, like me, use a solution that includes almost 60 sub-projects.. That could become quite troublesome :).
And if that solution uses a Silverlight frontend, well.. A rebuild solution then seems to take you through the nine circles of developer-hell and back.
I found myself having a lot of waiting-time to fill. After finishing my fifth cup of coffee, I decided to take matters in my own hands!
MsBuild to the rescue !
After browsing the web, I found how to manually trigger msbuild as an external tool to compile your solution in parallel.
And even though most build time problems are related to IO speed; this is a simple solution that only takes a couple of minutes to implement.
More details can be found in the following post by Scott Hanselman: http://www.hanselman.com/blog/HackParallelMSBuildsFromWithinTheVisualStudioIDE.aspx
Using this solution, in combination with setting Copy Local = False, reduced my compile time with approximately 50% !