According to Blabbermouth, Josh Homme, frontman of Queens of the Stone Age, is said to be collaborating with rock legend Dave Grohl and Zeppelin bassist John Paul Jones. Homme's wife Brody Dalle commented on the project, saying that she is "not at liberty to talk about it, but i think [the project] is pretty f*cking amazing. Just beats and sounds like you've never heard before."
While this is a trio of absolutely epic proportions, remember that none of them are strangers to each other in the least. Grohl played drums on Queens of the Stone Age's breakout album, Songs For The Deaf, and John Paul Jones conducted an orchestra for Foo Fighters' performance of "The Pretender" at the Grammys.
In any case, this is definitely a project to keep an eye on, since there is almost zero chance of this being anything less than spectacular, and Grohl and Homme have a reputation for being great collaborators.