Microsoft and Yahoo have both been trying various tactics to overtake Google as search king the past few years. It's no secret that Microsoft will stop at nothing to reign supreme, and it seems own tactic they are considering is to buy Yahoo. After being defeated for the DoubleClick purchase, Microsoft may go a step further and sink $50 Billion into them. That's not saying Yahoo will say yes, just that negotiations are happening. Even with Yahoo at their side, however, they would not have the majority share in the search and online advertising market. They'd certainly have a step up, though, considering Yahoo is currently holding a large lead over MSN.

What would a merger of Microsoft and Yahoo bring? How would it impact their messengers, their webmail and a host of other things? A lot to think about.