Adding on to their introduction of the latest Lotus Notes suite for Linux, IBM is now offering Lotus Sametime Messaging for Linux platforms. Designed as an instant messenger for business use, Sametime is something you probably haven't heard of unless your company uses it, but many businesses rely on software such as this for intra-office communications. IBM's goals are to provide a configuration path that allows a fully Linux-based office:

"With IBM Lotus Notes for Linux and now Lotus Sametime support for Linux, all of an organization's key collaborative business applications can run in a 100 percent Linux environment," said IBM Vice President of Lotus Products Ken Bisconti.
The article mentions the lack of Sametime support for Linux being a “stumbling block” for some companies wishing to adopt the OS. Exactly what percentage that would be would be interesting to find out.