No charge. You can also just ask your cabin stwewart.
SS Norway (12 times) '85 - '97; Radiance OS 06/01; Island Princess 11/04, Grand Princess 11/04/05, Golden Princess 7/21/06, Golden Princess 2/24/07, Explorer of the Seas 12/23/07, Island Princess 11/15/08
Yes, that's what they're called and there's no charge. We've always been very comfortable in the Princess beds, but we like a firm bed. If you're going to ask for an egg crate you need to ask your Room Steward for it as soon as you meet him/her. They do run out.
"A truly happy person is one who can enjoy the scenery on a detour."
Golden Princess 2009 Carnival Conquest 2010
Grand Princess 2010 Island Princess 2011
Grand Princess 2011 Carnival Magic 2012
Carnival Dream 2012 Island Princess 2013
Carnival Magic 2013 Carnival Legend 2014
Carnival Magic 2015 Coral Princess 2015
Just asked my steward on the Emerald last November as soon as I got on board. They're foam with indentations that look like you could put eggs in them - i.e. "egg crates" and bigger than chicken eggs ... I found them very comfortable.
I cruise the Emerald Princess, Eastern Caribbean on April 16, 2012
my last bed n the Tahitian Princess was so bad I asked for a new one which they came up with a couple days into the trip.
They did not offer me an egg crate but I would expect there would be NO charge for it.