We're hearing some chatter that Clear Channel (CCU) will make a bid to buy XM Satellite Radio. This inspired a bit of a spike in activity this morning as you can see.

We haven't heard anything else on this, but as news develops you'll find out more here.

UPDATE:
Y'know, this story just stinks of bullshit. The more and more I hear on it, the less and less likely anyone thinks it'll happen. It has even less credibility than the XM and SIRIUS merger. Sorry if anyone soiled themself over it..