Yahoo has bought MyBlogLog, a Web site that builds online communities around the blogs people like to read. This purchase is Yahoo's latest in a string of acquisitions of sites offering social networking, including Flickr, Del.icio.us, and Upcoming. Financial terms weren't disclosed. ...

EBay said last week it plans to buy ticket reseller StubHub for about $310 million in cash. The deal is expected to close later this quarter. ...

Sprint Nextel announced it had a net loss of 300,000 subscribers in the last quarter and plans to lay off 5,000 employees. The company's stock plunged 10% on the news Jan. 9. ...

Hannah Engineering, Rajant, and Sanmina-SCI say they've made the first wireless phone call from a thousand feet inside a coal mine. The jointly developed system was tested in mid-December in a former mine near Pittsburgh that's now used for research and testing. Wireless service inside mines could greatly improve safety, letting miners communicate during a disaster. ...

The volume of spam rocketed in December, accounting for a record 94% of all Internet-sent e-mail, message security company Postini says. The company blocked 25 billion spam messages aimed at 36,000 clients in December, an increase of 144% over the same month in 2005.