Although we don't believe in timing the market or panicking over market movements, we do like to keep an eye on big changes -- just in case they're material to our investing thesis.

What: Shares of aviation electronics and communications maker Rockwell Collins (NYSE: COL) got a 10% boost Friday on news that rival aerospace firm United Technologies (NYSE: UTX) is raising cash to make a big acquisition.

So what: Rumor has it that UTX is lining up creditors to support a $20 billion purchase offer. Of course, Rockwell carries only an $8.6 billion price tag today.

Now what: How likely is it that United Tech would pay a 130% premium to own Rockwell? Not likely, I fear. Then again, rumors have a tendency to grow in the retelling. Perhaps UTX is not really raising $20 billion, but only $10 billion? That would make Rockwell a more likely target. Or UTX could be planning to acquire ... nobody. Maybe what it's really up to is raising cash for a share buyback a la Intel (Nasdaq: INTC)?

For now, your guess is as good as the guesses of everyone else gambling on a UTX-sponsored buyout.

Who will UTX buy? Will it buy anyone at all? Add the stock to your watchlist, and read along as we discuss the question.