Mark Cuban wrote a fascinating post on his blog, a scheme to kill Google by offering the owners of the top-ranked sites money to remove themselves from the index.
It's an interesting idea. I see a couple flaws, but they are interesting flaws.
Morally, I think it's abhorrent: it would fundamentally make the Internet a worse place for the sake of cementing an artificial lead by a company that by and large wouldn't do good things with it. Basically, it would be buying rather than earning a monopoly.
However, for a handful of popular sites, that much money could mean the ability to offer a lot of things they currently can't. Moreover, it raises an interesting question: Search right now is built on the backs of the popular sites, under the assumption (mostly correct) that for each site, more traffic is better than less. Advertising revenue is not split with those sites -- they have to find their own funding models, but there is the promise that users who come to a site by being guided by a trusted search engine are more likely to look at ads, spend money, and generally not waste bandwidth.
For one thing, this risks playing out as a large-scale Prisoner's Dilemma. If Microsoft approaches a thousand sites with a million dollars each, then many of them will sit there thinking, "If I defect from Google alone, I get a million dollars... and then very little traffic. Meanwhile, my competitors will get the Google traffic that would have gone to me." For many retailers, if they make the move but Amazon doesn't, then they're sunk. It doesn't matter, though, we can postulate a number that would make it worthwhile. After all, if Bing winds up the top search engine as a result of the bribes, then these retailers won't be losing much money.
But, what if Microsoft ceded to Google the top retailing sites, and went after specific markets? With a scheme like this, Microsoft could potentially make itself the go-to search engine for gaming. EA is hurting right now, a few mil would definitely help their bottom line, and most of these companies develop either for XBox or PC. Game review sites don't exactly operate on great margins, ditto sites that offer forums, walkthroughs, and cheat codes. And something like this could jump-start the indie games movement in a huge way, providing the kind of money most of them only dream of. Microsoft could be seen as a benefactor of the industry in this case, and there would be a lot of spillover: users who bring up a Bing window to look for information on an upcoming game might leave it open to search for someone selling that game.
Aiming at less technical markets, Microsoft could do something similar for sports. Or, it could go after non-English sites. Cornering the market on, say, Italian language sites could be much easier, though probably less lucrative.