When my cats and I first moved to Atlanta, we settled in a nice little apartment. First I had the couch at a right angle to the large front window, and I put a small table in front of the window so Lewis and Ebony could sit there and watch the goings on outside.
A few months later I rearranged the apartment and put the couch in front of the window. That ended up being a mistake, because the kitties have a mind like a computer memory and learned something they have since never forgotten: the back of the couch is an awesome place to sleep. They never used to get up there before but once it became the Prime Spot for Window Watching, they soon settled themselves in and wouldn't move. About a year later, the apartment was rearranged again, and the couch came away from in front of the window. Since then, it has never been in front of the window, but alas - it was too late. Their favorite spot to sleep has since been on the back of the couch. It's great - they can see everything that's going on, be closer to our eye levels (especially when we're sitting), and it's comfortable to boot.
A few months ago we finally saved enough money to buy a new couch and loveseat. My thoughts were that with this new couch, which had a different type of back cushion, the cats would find a new place to rest.
Who was I kidding? Once they got over their fear of the new couches (really, why were they so scared of them?) they happily settled onto the back. And now they have pushed the cushion down enough that it's more comfortable and less attractive for us. Sigh.
I need to find something that will keep them off the back of the couch. I'm thinking that perhaps some tub mats with the suction cup side facing up would be good. I've also heard that most cats will avoid tinfoil. Or perhaps I should just not worry about it, because let's face it - cats will go wherever they please, isn't that true? We'll see.