Okay for everyday maintenance -- you can even use eyeglass spray to clean them.
The SkipDoctor is at a good price at $23.00 at Amazon and for $5.00 more you can get the motorized version (really would be worth it not to have to crank the dang thing). If anyone orders it, they can go through the Portal Shop on the link above and site will get credit.
THEN SKIPDOCTOR at AMAZON
I'm not sure if the site gets credit when you follow a link here and order. Craven can answer that question. Anyway, I highly recommend it as I've save many, many CD's, DVD's and CDRom with this inexpensive little unit. I'd order and extra polishing wheel while I'm at it. I also will sometimes use a fine abrasive plastic polish (it's actually baking soda in a gel) if I really want to polish them up and their finishing spray adds more of a shiny finish and protection (the wheel leaves some vague tracks on the surface but it doesn't really bother the penetration of the laser).
I used to use a similar material that is on the wheel to polish the ends of plastic fiberoptics in an R&D lab.