I have always been curious about ceramic knives but not curious enough to pay a steep price for what reviews say is a deft, but fragile, instrument. Ceramic is very hard, so they never need sharpening. Indeed, they can't be sharpened so the edge had better last forever. Unlike metal, ceramic is easily chipped. And once damaged, they're trash because unlike a metal knife, chips and nicks can't be ground away. So I am reluctant to spend hundreds of dollars to augment the knives I already love.
Then I stumbled on a ceramic paring knife — for about $9. Dealextreme is an Internet seller of very inexpensive gear. They sell computer and camera accessories, toys, gadgets, and household items that are manufactured on the cheap by Asian manufacturers. Most of what they sell is pretty good quality and the prices are amazing. Shipping is free but it usually takes a couple of weeks. I ordered one and I have to say, I was impressed. The quality is pretty good and it is quite sharp. It will presumably remain sharp for years, and so far hasn't been damaged.
I also bought a ceramic vegetable peeler and was less impressed. A peeler has to be very sharp and this wasn't quite sharp enough. Still, it was mere $3.
All that said, I still am not a ceramic knife fan. They don't need to be sharpened but I don't find sharpening my knives much bother. I use a steel on them every time and only need to sharpen them a couple of times a year. Except for the eversharp edge, a ceramic knife is no better than a well-sharpened metal knife. So I'll probably buy another cheap ceramic knife but they won't be displacing my favorites.