If you're like me, you're a little intimidated by the prospect of sharpening your own knives, but are unwilling or unable to send them to a professional sharpener. Help is at hand! Go here for an absolutely excellent tutorial on knife sharpening.
Curious as to how you all test your knives for sharpness. I test mine as I do when I test my fish hooks. If the hook point catches on my nail, it's sharp. Same with knives. If I scrape it across my nail and it catches, it's sharp. The more acute the angle it catches at, the sharper it is.
Of course, I don't think painted and acrylic nails would work too well.