The swaybar limits the jeep's front end from dipping down or rising up while turning, making for a much more stable drive on the road. When off-roading, it severely limits wheel travel (and traction in many cases), or how far the wheel can move downward or upward when going over obstacles. If you've ever seen pix of folks showing off their "flex", you'll see what a difference disconnecting the swaybar can do for you offroad. In addition to wheel travel, disconnecting the swaybar allows the jeep to remain more parallel to the ground on eneven ground.
You can buy a set of "quick disconnects", make your own, or simply unbolt the links and tie back the swaybar. You'll want it back when on the road, especially on the highway, because a sudden sharp turn could get hairy without it.
In this pic, the disconnects are the black bars (you can only see one) to the left in front of the coil spring. Note the pull pins:
This is a very lame poser shot of my XJ with the swaybar disconnected, but it is a good example of what I'm talking about. I had just put them on and wanted to check out the wheel travel, so I disconnected them and pulled up this bank. Notice how the Jeep is sitting straight and the wheel is drooped low. The drivers side wheel is stuffed in the wheelwell.
With the swaybar in place, my jeep would have been sitting at an angle and there is a good chance the rear wheel would be raising up off the ground.
If you are interested in making your own, ask Mingez how he did his. He'll probably be able to explain it better if I didn't make any sense.
There's some good info on this subject here on Jeepz in previous threads. I would do a search on swaybar disconnects on this site, it has been discussed alot and you may better answer your questions and maybe get a few ideas.
hope this helps.
TC