Theory of Everything? Physicist/surfer Garrett Lisi may have found a way to unify all the major particle and forces of nature, including gravity, without having to rely on dubious multi-dimensional string theory. Plus his theory may be testable in the near future. His theory predicts:

...more than 20 new particles not envisaged by the standard model. Lisi is now calculating the masses that these particles should have, in the hope that they may be spotted when the Large Hadron Collider - being built at CERN, near Geneva in Switzerland - starts up next year.

Here's a related article. Here's the link to his paper. (Click on the "PDF" icon on the upper right for the PDF version.) And a link to a semi-technical explanation (with video).

(FWIW, I once met him several years ago at a dinner party, back when Diana and I lived in San Diego and he was a PhD student at UCSD. He was a friend-of-a-friend, and he struck me as an extremely intelligent man. So although my math background is not strong enough to enable me to assess the merits of his theory, he would be a plausible candidate to have come up with a revolutionary new theory in foundational physics.)