Visual Studio Builds per day

Question

Is there any way to log the number of builds done during a development day in Visual Studio, or anywhere we can hook into something to get at the metadata?

I'm curious how many times on average I build/day * how long it takes per build...

Any thoughts?

UPDATE: sorry for the lack of details...and this exercise is purely academic

With a solution that has 14 different projects (1 is a web site). I am constantly building the entire solution (Ctrl + Shift + B). It would be interesting to find out not only the number of times I build during the day, but how much time is spent waiting for a build to complete...

The optimal solution would be one that doesn't require a change to the solution's projects itself. (pre/post build events) I don't want to have to add/undo changes before/after check-ins.

(The nant/other solution is sounding like the answer, I guess I could map that to a shortcut key and not have to leave VS to do the build)

Any other suggestions?