It's an interesting hack. As Edelman points out, Crackle should be doing a better job vetting its partners. What would a fix on the technical side look like, though?
The end to end principle tells us that advertisers shouldn't pay for anything but clicks (and even those are suspect) because display alone is impossible to verify. However, one could imagine HTTP including a request header specifying what size window the result would be displayed in. That is perhaps an unfortunate mixing of transport and presentation layers, but I'm sure it would be otherwise useful for web developers.
I'm not really happy with iframe clipping in general--- it occasionally goes wrong and removes something I wanted to see. And 1x1 web-bugs are annoying anyway. Maybe the browser could highlight these uses in some suitably-annoying way that would discourage their use. ;) The more I think about it, the more I'm convinced that my web experience would not suffer in the least, should my browser refuse to load anything contained in a 1x1 frame.