When even the world's best search engine can't turn a profit ...

Google is considering creating subscription versions of its popular search engine that could target academic and corporate clients, a source said Thursday.

The Mountain View, Calif.-based company is evaluating new "vertical markets" as a means of increasing revenues, according to a source within the company. Among the considerations are new niche searches for periodicals, medical information or technology that Web surfers or companies would pay to use.