Best way to clean CD's?

Mapleshade has a couple of excellent products which can not only get it off, but substantially improve the sound. Check their website for tweeks and call there tech line if you have questions.

Their are CD enhancers but on the cheap you cannot beat a bottle of eyeglass cleaner , wiping from the center out, with a soft cloth {a cotton t shirt} works well .

Dawn dishwashing liquid and a cotton cloth.

I use the Mapleshade Products with great results. You will clean them and improve the sound also. Micro Smooth and Optrix will do the trick.

The eyeglass cleaner with lint free cloth (or microfiber) is about the cheapest wa to do it. You can get both at Sam's club or Walmart, which can keep the price down.

The next level up is probably the Novus cleaners, which are for polycarbonate surfaces, which is what CDs are. They also have a scratch remover that works pretty well. But the stage one clean with a lint free or microfiber cloth will be all that you need to remove fingerprints and smudges.

The next level up is something like the mapleshade cleaners. But if you're going to go that far, also get their ionoclast gun which will remove static buildup from the application of the cleaner (plus the static buildup that was already present on the CD). The effects of ionoclast should be audible in most resolved systems with a trained ear.

Oh yeah, wipe the cleaners off in a raduis patter away from the center hole to the edge. Never wipe them concentrically. That can damage them.