He hit .294 for the Red Sox after he was dealt to the club in the Nomar Garciaparra trade on July 31st of that year. He played a solid shortstop, and was a big reason the Sox vaulted into the Wild Card lead that August, and eventually into baseball history.
Cabrera left as a free agent after the 2004 championship, and the Red Sox wound up drafting Jacoby Ellsbury and Jed Lowrie as compensation for his exit.
From the 2004 team, there are only seven active players left: Jason Varitek, Tim Wakefield, David Ortiz, Kevin Youkilis (still with the Red Sox), and elsewhere in MLB: Johnny Damon, Bronson Arroyo and Derek Lowe.
All the best in your retirement, OC. We'll always remember your slick glove on that immortal club.