The nice crackling effect comes from a brand called "Real Flame", which is more expensive to get from their web site. I've found it for cheaper on-line at Target, and I also found it on Amazon for the same price. While looking up the links for you I also found another brand called "SunJel", Which also looks to be more expensive for the cans, but which also sells refill bottles for their canisters. I haven't tried them, but they sound like the same basic stuff (Though I can see SunJel is clear where as Real Flame is a reddish gel), and they do not suggest reusing the cans more then 4 times.