I LOVE the TidyCats Crystals BLEND litter. It's clay litter with crystals mixed in and it keeps my 4.5 cats (a neighborhood stray is adopting us) and their poo under control without breaking the bank.
I get it at petsmart.
May I ANTI-RECOMMEND Feline Pine? Avoid, avoid, avoid. My cats, after a decade of faithful litterbox use, went on a going-outside-the-box RAMPAGE because of that stuff. AND one got a bladder infection (probably from holding it!).... And my friend's cat (this is darkly humorous) had her bum go totally bald as a result of it.