Since yesterday, a new Google service called Google Base leaked and has since been off and back online repeatedly. The service is similar to craigslist.org in that you can put up things like items for sale and other people can search for them. From their page:

Google Base is Google's database into which you can add all types of content. We'll host your content and make it searchable online for free.

Examples of items you can find in Google Base:

• Description of your party planning service
• Articles on current events from your website
• Listing of your used car for sale
• Database of protein structures

You can describe any item you post with attributes, which will help people find it when they search Google Base. In fact, based on the relevance of your items, they may also be included in the main Google search index and other Google products like Froogle and Google Local.

The current categories of things you can post are: Course Schedules, Events and Activities, Housing, Jobs, News and Articles, People Profiles, Products, Reference Articles, Reviews, Services, Travel, Vehicles, and Wanted Ads.