[Ravioli]

Here's a method that's used by professionals such as National Geographic photographers.

Breath on the lense. (Make sure your mouth is clean) Use a lint free cloth or any cloth you're comfortable using on your lense and gently wipe the lense with a circular motion. It will clean the lense. I accidently lightly scratched my lense with a dust blower and it totally removed the light scratch mark while cleaning the lense itself.

I highly recommend this method for cleaning. It beats lense cleaning fluids!