Google's AdWords blog just announced that the AdWords reports now give you the ability of Estimating invalid clicks. Yea, you got that. Google will be showing you which clicks they have deemed "invalid" and credited towards your account. Great move on Google's part, IMO. First to do so and I hope the other PPC engines follow. More on invalid clicks here.
How do you see the data, just add them to the reports as so:
This goes great with Google's invalid click efforts being considered resonable, just one more step in the right direction. Chris also posted a topic on click fraud this morning, asking if you are worried about click fraud? Well this may just help a bit.