I can't believe it took me until now to stumble across Paul Chek's excellent three-part 2004 article on the importance and mechanics of the squat. (Check 'em out here: Part 1 / Part 2 / Part 3.) I'm convinced that squats -- with or without a barbell -- are among the handful of the best exercises one can do.
So if you're P90Xing: SQUAT!
Or if CrossFit's more your thing: SQUAT!
Want to hang out on a street corner in Asia like the locals? SQUAT!
Stiff and sore? SQUAT!
A disciple of the Primal Blueprint? SQUAT (to poop and stretch and exercise)!
The best thing about squatting? It's easy -- all it takes is a little practice.