What's the safest way to clean a fingerprint mark on the lens of a digital camera?

I've noticed that a "lint free cloth" sometimes causes faint
scratches on glass. The special papers sold for cleaning
lenses seem somewhat hard for this purpose.
"Common wizdom" I heard says "blow on the lens, and with a soft cloth wipe spirally from the center outwards".
I did so once on a film camera and effectively rendered it useless as a myriad tiny scrathes appeared on the lens which
was smudgy but intact before.

A regular glasses cleaner with the proper type of lens cleaner will work. I'm not talking about any kleenex style ones or many of the fiber ones that come in packs at the store. These are fabric ones that are sort of shiny and very smooth....they don't have the fibers that will scratch because they have very high thread counts. Hope this helps, it works for my cameras as well as my glasses.

just keep it in a bucket filled wid acid.....
nd it will be cleaned forever......lol

http://www.ritzcamera.com/product/221660...

works like a charm and will protect your lens.

best way is to clean it with a piece of LEATHER ,i will shine as new without nay harm .....

Always use a lens cleaner cloth or a lint free cloth. This is the best way. DO NOT use any substances on the lens as it can damage the lens.