The Pure Google Links link at the page referred to at Boing Boing was dead, but Kronoss.log has the script. For convenience, I’ve mirrored it here.
Edit: Since the original doesn’t seem to be working for me at least, I’ve modified it so that it does: Aggressively Pure Google Links strips all onmousedown attributes from links on Google search results pages (the way the original seems to have been implemented some time in the past). I’ve not done enough testing to say this is fool-proof and risk-free, so install it on your own caution.