I can understand doing so for scrypt-based crypto, but is there any point in doing CPU mining on a SHA-256 on any pool? Seems like just a waste of time/energy -- but I guess the OP is just using it for testing a netbook.
Maybe as a stress/burn-in test for CPUs-- Or has that been suggested already?
You are right, it isn't viable. But, sometimes we do things because we can not because it makes sense. There is a Hobby aspect to mining. CPU mining can be a learning experience, even if all that you learn is that you shouldn't do that.

What kind of hobby is looking at your processor burning a hole in itself for no profit?

Try some Quark-clones or PrimeCoin (Protoshares have been overtaken by GPUs, I think). Mining Bitcoin with a CPU is like going against Deep Thought with a dollar store calculator.