Going into tonight, Cristian Guzman leads the league in batting average, Josh Willingham leads the league in on-base percentage, and Ryan Zimmerman leads the league in slugging. (Andre Ethier leads both Guzman in BA and Zimmerman in SLG but doesn't have enough at bats to qualify.)
The 1959 Detroit Tigers are the only team in MLB history that has had three different players lead the league in the so-called "rate" triple crown categories in the same season. Harvey Kuenn won the batting title while Eddie Yost led the league in OBP and Al Kaline led the league in SLG.
There are a number of teams that have split the BA, OBP, and SLG titles between two players, but none recently:
1933 Philadelphia A's: Jimmie Foxx (BA and SLG), Mickey Cochrane (OBP)
1893 Philadelphia Phillies: Billy Hamilton (BA and OBP), Ed Delahanty (SLG)
1888 Chicago Cubs: Cap Anson (BA and OBP), Jimmy Ryan (SLG)
1887 Detroit Wolverines: Sam Thompson (BA and SLG), Dan Brouthers (OBP)
1877 Boston Red Stockings: Deacon White (BA and SLG), Jim O'Rourke (OBP)