Running a python program during idle time only

[los]

Yes it should.  The problem is that I notice a loss in performance when
the program is running at 100% CPU.  Even though it is nice, if you try
to open up new applications, or switch between them, you notice your
computer lagging a little bit.  That's why even though I'm not using
the cpu that much as I'm just reading my email, or browsing the web, I
wouldn't necessarily want the indexing program to be running at full
pace.  If you use google's desktop program, you'll notice that once the
computer has been idle for a few minutes your CPU will go to 100%, but
as soon as you move your mouse, or hit a keystroke the cpu will drop to
5-10% usage.  That's the behavior I'm trying to achieve.

Thanks David for your suggestions.  That seems to be what I was looking
for.  I'm going to try to incorporate those changes in my code and see
what I can come up with.  Thanks for everyone who responded as well.  I
really appreciate it.

-los