I noticed a person said this so I thought I'd put in my 2 cents worth.
 
"The litter I use is 10 bucks for a 5 pound bag."
 
What I use is wood pellets $4.35 for a 40 pound bag.
 
What they are is for a wood fire stove but instead of traditional logs they
use a bin that acts as a feeder and able to use a thermostat or a switch
that turns it on and off.  The stuff is available by calling hardware or
fireplace businesses.  They are harder to find in the summer since its the
off season.
 
Bruce
[Posted in FML issue 3094]