They work just as well as the ones that cost a buck a piece, but cost nothing. If you have sawdust and your wife burns candles, you can whip a batch up in just a few minutes. Melt wax from spent candles in pan, add sawdust, mix thoroughly, transfer mixture to plastic disposable container (cool whip bowl) and tamp down evenly and firmly. Put the bowl in the freezer for 20 mins or so. Remove from freezer and pop it out of the bowl, ready to burn. I don't recommend making them on anything but a glass top stove. Oh yeah, and they smell nice too, like every candle she's ever burned at once.
If I can commandeer an ice cube tray, I think I can make some cube sized nuggets. I'd like to do it just one more time and be done for the winter. I know she has a shoe box full of spent candles around here, just gotta find them. Will be nice for those reloads that take a while to go poof. They're actually kind of fun to make.
Bunch of us that make our own on here. I use egg cartons (not the styrofoam), sawdust, and whatever wax I get a hold of. Might buy some Supercedars next year.