How can I put chocolate fondue in the base of a fruit topiary?

I'm planning my wedding and would like to have a strawberry topiary centerpiece at each table with chocolate in the base pot to dip in. I thought it was simple at first but how can I keep the chocolate warm and melted??? or at the very least are there small warmers I can put the chocolate in separately at the tables?How can I put chocolate fondue in the base of a fruit topiary?
http://www.crateandbarrel.com/family.asp鈥?/a>How can I put chocolate fondue in the base of a fruit topiary?
They have the small fondue pots and even the small chocolate fountains. The problem with the both of these are that they need to be plugged in. Using tea lights will cause the chocolate to burn. I know melted chocolate is more appealing,but maybe if you did something like a ganache that holds heat a little better and is still edible as it cools