I didn't start having this problem until a few years ago with my last pair of eye glasses. It seemed no matter how much lens cleaner I used or wipes I would still get these greasy smudges that wouldn't go away. It's like they would just spread around. They might even look clean until I put them on, and then I'd still notice blurry spots. I got pretty fed up with it.

Single use cleaning wipes work pretty good, but sometimes you just don't have one on you. In a desperate moment one day, I tried something that turns out to work better than anything: dish soap.

Run some hot water, put a drop of dish soap on each side of each lense and you can even rub it with your fingers. Rinse it off, and then pat it dry (don't wipe it). They will sparkle, and you've got a clean pair of glasses.