I had this problem!
We rescued Sylvester - he was dumped at the farm my husband worked at and we ended up with him when my husband and the other workers noticed that his paws were bloody. Turns out he was declawed and was trying to get away from predators and other cats and had broken his toes because he could not use claws.
Anyway, he was thought to be about 2 years old, and when I got him home I slept in the guest room with him (I had him separated from the other cats until he could be tested for FIV). He peed on me that night in the bed. Once he was tested and checked for UTI, he would pee on us if we were napping and he started peeing on the leather couch and the rugs. We had 3 other cats at the time and one of them started joining in on the fun.
What cured him for me was using Cat Attract or Kitten Attract litter. I did also use Feliway and tried Prozac for a very short time, but I really think it is that litter that works. When I brought a feral cat in, he was peeing in different places in the house. I added a couple of litter boxes and put them near where he was peeing. I used the Cat Attract and gradually moved the litter boxes where I wanted them (like over a period of weeks). I now have 6 cats in the house and have 3 litter boxes - 2 in the laundry room/hall and 1 in the den. I have the 1 in the den so that I can put a baby gate up and keep the dogs out (I have 5 dogs) to give the cats more privacy.
Sylvester has not had an accident since we made these changes - it has been 3+ years. The others have not had accidents either. I buy the Cat Attract once a month now and mix it with the Natures Miracle unscented multi cat litter (the Cat Attract is more expensive) and it continues to work for us.