A search engine could be distributed and any person running a node would be rewarded with a "SearchCoin". In other words, combine the financial rewards and distributed nature of running the BitCoin network but with a search engine as the proof of work.

The question is, how do you prevent bad actors from delivering biased results or malware to users? Should a client query N nodes and only accept the result if they match? And if the search algorithm is public, is it still possible to prevent that algorithm from being gamed by SEO results?