Just like its containers, cat litter can be replaced by several different things that share its properties. If you are trying to cut down on expenses, you can try using junk mail and old newspaper (in shreds) instead of commercial litter. Regular sand might cut it too.
Plus, if you have a workshop or a farm, using wood shavings or chicken feeds is highly recommended.
We have already prepared an article that goes deeper into the topic of “What can I use instead of cat litter.” Just check it out if you want.