The Higgs Boson
Or, how to fake an understanding of the Standard Model at cocktail parties. Brian Doss of Catallarchy links to a page offering five one-page explanations of what exactly the Higgs particle is. All five are surprisingly clear and accessible, and even fervent math-haters should find them easygoing.
Those in need of a more nuts and bolts treatment are welcome to look here for a more (much more) mathematically demanding treatment; you'll find there all the group symmetries, gauge transformations, tensors and Lagrangians you could ever want.