Been investigating a Rear Axle Ratio swap. 2LS's come with 2.97 instead of the 3.27. Seen many people swapping out for 3.55's or higher. I'm gonna put that on my list. Have also seen people just swapping out the whole rear end. I've done that plenty of times on older cars.
The other project I'm looking into is enabling Sport mode for the 2LS. Found an interesting thread here on Camaro5 about someone who pulled it off.
http://www.camaro5.com/forums/showthread.php?t=340877
Update: Found the 3.55 gears by Richmond for my car for $580. Maybe a project for the spring.