Apple announced a preview of Xgrid technology today.
Apple today previewed Xgrid, a computational clustering technology from Apples Advanced Computation Group (ACG). Xgrid helps scientists and others working in compute intensive environments to fully utilize all IT resources, including desktops and servers, by creating a grid enabled virtual IT environment that takes advantage of unused computing capacity to run batch and workload processing.
Xgrid is available as a free download from Apple starting today, according to the press release.
Xgrid was first trademarked in 2002, spawning much speculation.
More info is available here: http://www.apple.com/acg/xgrid/