I was wondering if anyone has found any good alternatives to the rather spendy Pett Toilet bags. They are very nice with the sealable storage bag and powder already in place, however it's hard to swallow the $2+ per bag pricetag. I know they have the powder available in bulk form so one could find some nice small biodegradable bags. I'm not sure if there's a less expensive alternative out there that I'm missing.
What do you use?