SIMPLE SOLUTION: We put them on our harvest dinner table in blue glass bowls filled with water, where they float and they look just beautiful. Here's how to make your own:
Food markets that carry local harvest produce often offer miniature pumpkins. They are 3"-4" across. Buy six to eight of these pumpkins, and the same number of votive candles (pure beeswax votives, if you can find them). Hold a votive candle over the top of the pumpkin and trace a circle around it. Using a knife, carefully cut out the circle so that a votive candle will fit into the hole snugly. Repeat with all the candles. Fill bowls or pails with water, light the candles and float the pumpkins in the water.
http://www.care2.com/greenliving/make-floating-pumpkin-candles.html