This rig might, in a way, remind you of the wacky rig (http://www.vingle.net/posts/332261-Best-Bass-Fishing-Rigs-Wacky-Rig). The difference lies in the fact that the wacky rig, in its typical presentation, is horizontal and you fish it vertically.
On the other hand, the Neko rig shows the plastics vertically while you fish it horizontally. Still, you can see some similarities I think.
The basic Neko rig is easy to set up. First, put your hook on the end of the line. Then, put this hook through the middle of your plastic worm or whatever other plastic bait. Then, put a nail weight or other weight into the tail of the worm. What this does is pull the tail down, but when you jiggle your rod, the worm will twitch forward but still be vertically position. Definitely a unique look. Check out the video on slide #2 to see this in action.
There are actually some specific weights made nowadays to put into the worms tail, and even some specific plastics made to be rigged Neko style. While some people use nail waits, others fine screws more effective because they don't fall out as easily, and they're cheaper!