Well, if you can call sitting in a tube and floating down the river a sport... there are several places to go tubing that are within 2 hours of Baton Rouge, but the closest is on the Amite river just outside of Denham Springs (Tiki Tubing). You can "float the river" or paddle down in a kayak. It's a great way to hang out with friends and relax, but I'm always suprised because at the end of the day (of doing nothing) you get exhausted!
Equipment: Bring refreshments and some flip-flops that you don't mind loosing... you rent the tube (or kayak) from Tiki Tubing. Just don't bring any styrofoam or glass.
When the river is not at flood stage (normally during the summer and fall, it is possible to venture down the other side of the levee "the batture" and walk up to the river's edge.
This affords excellent opportunities for just taking a hike, for mountain biking, dirt biking, and for the bravest of souls--fishing.
(Notice the dirt biker in the photo.)
But note even though the river looks peaceful and serene, looks can be REALLY deceiving. It is DEEP (approximately 180+ feet in some pockets), and the currents in it are not to be played with. Since I have lived here, two kids have been pulled under and drowned by the mighty Mississippi. So if you are going to fish, do it from the riverbank!
Equipment: motorbike; mountain bike; old boots (or shoes you don't mind getting muddy); fishing pole and bait
A night game at LSU's stadium is so awesome. 92,000 REALLY excited fans. Fans here are like fans of Premiership Soccor leagues in the UK... they live and die by their team. The crowd is SUPER load (actually registering on a seismograph) and wild. If you get the chance to be in the student section, DO IT! It is the best spot for college sports on the planet (when LSU is doing good, of course).
Equipment: Alcohol... if you can sneak it in, which is one of the great LSU student planning accomplishments. We will come up with anyway to get the stuff in!