Cast iron pan on ceramic electric range

I've never had a problem with my glasstop (non-induction) cook top.
It's at least 15 years old and well used...and will still shine up with elbow grease, a razor blade, and glass polish.

If you're really worried...get a tabletop gas burner from an Asian store. Like this one:
http://www.amazon.com/Max-Burton-Table-Burner-Black/dp/B000G6S8Y8

I wouldn't worry about using it for long simmers, but I use mine all the time for Wok Cooking as a round bottom Wok and gas control is the best.
One type of cast iron I would NOT use on a glass top is a campground type dutch oven---which has legs; which sit on coals or in a fireplace.
The legs would make a thermal point on a glasstop.

I had two different ceramic cooktops over about ten years, and I also have a couple of cast iron pieces that I simply have to use. I never had any problems.

Given Hilarybee's experience, my suggestion would be to limit your use of cast iron to when you really want to use it, be careful not to drop a heavy piece onto the surface, don't place a cold pan on a hot burner, and don't place a hot pan on a cold one. To avoid scratching (again, never a problem for me), check you pan bottoms to make sure they're smooth, and avoid sliding them around to much.

Oops! I just realized you said ceramic cooktop, not induction cooktop. Never mind! :-)

Food odyssea, you probably know this trick already, but when shopping for new pots/pans for induction cooktop, bring a magnet with you. If the bottom of the pan holds the magnet, it's OK to use the pan on an induction top. (At least, that's what I was told by the Viking salesperson.) Also, if you're buying a full set on sale, etc. you actually have to check each pot/pan with the magnet. A friend learned that apparently no all in a set are created equal. I think the need to check every item in the set probably applies to less expensive sets and not the higher-quality brands.

I disagree with Maedl. Do not put a cast iron pan on an induction cooktop. I did this, and not only did I scratch it--I completely cracked the cook top. My mom had a Jenn Air and she cracked hers with a cast iron pot, too. We should have learned from each other but did not. Go to a discount goods store--Homegoods, Tuesday Morning, etc. and get a pan approved for induction cooktop. Small investment if you consider the cost of replacing your entire range, as I had to do.

I have used cast iron on a ceramic electric stove for seven years and the stove top still looks fine. I don't notice any additional scratches.

While it's nice to use your kitchen carefully, if you treat it like a trophy kitchen, you won't get much use out of it. Kitchens are made to be used, not looked at!