Mercury Computer Systems announces a Cell Accelerator Board (CAB) for PCs at the Siggraph 2006 conference.

As you know the Cell CPU is also used in the Playstation 3. Mercury enables you to leverage the power of the Cell BE processor with 2.8Ghz in your PC.
The PCI board gives you 180 GFLOPS of performance.
This Cell board is not for gaming though, it is aimed at rendering, ray tracing, video and image processing, and signal processing.
Prototypes of the Mercury CAB are now available in limited volumes. Production availability is planned for the first quarter of calendar 2007. Pricing for the Mercury Cell Accelerator Board starts at $7,999.
More details in this Mercury Systems press-release.