Google targets Craiglist with new Google Base service beta.

Launched as a "beta test" early Wednesday, Google Base has the potential to make instantly available a vast sea of content including — but not limited to — recipes, job ads, photos, DNA sequences, real estate listings and individual standalone databases.
Normally, it takes Web "crawlers" days or weeks to scour the Web and feed Google's main search engine with updated information, but they usually can't penetrate content buried in databases. This tool will make locating anything that's been uploaded nearly instantaneous, provided it finds users willing to provide the content.

from Yahoo!