Ok, here's my from dirt to shiny list.
First, use concentrated Simple Green on the playfield to remove grime, dirt, old wax, and nastiness.
For really tough spots get a Magic Eraser or major ball swirls, cut it into 2" x 1" x 1" strips, dab it with as close to 100% isopropyl alcohol as you can find (you should be able to find 93% commonly in drug stores), and rub with medium pressure in small circular motions around the wear. Pay close attention -- especially in areas where there is paint lifting or flaking -- and make sure you don't start pulling paint off with it. It's a very soft form of sand paper so to much force will damage a playfield (although I've never had any issues). The Eraser will leave a white residue behind which can be cleaned easily with another application of Simple Green.
Now it's time to Novus #2 the playfield. Work it over very well and then wipe off the residue. You can tell if there's still Novus left if the playfield feels tacky or sticky. Buff until it feels smooth and has a little bit of glisten.
Finally, hard Carnauba wax available from any auto supply store. Stay away from liquid. Wax it, wait 5 minutes, buff it. Redo. After that you should have an extremely clean, shiny, and high-speed table once again.
