Called saying they were from Renewable Energy Sources (or Solutions), a company that has called numerous times and been told not to call me again.  When I said I had told them not to call she became VERY rude, said "I don know that", "How's I supposed to know that" and just kept interrupting me when I tried to tell her not to call again.  After about 30 seconds of this I basically told her to kiss off, and hung up.
I have reported this company to the government do-not-call complaints section several times, but obviously they aren't doing anything to stop them.