Time for a semi-embarrassing confession. When Sandy and I were living in our one-bedroom postage-stamp apartment in Virginia right after graduation, with our two cats, we built a cat walk surrounding the living room. It was loosely based on
the Cats' House and it had a switchback carpeted ramp leading up one wall, three walls of cat walk with carpeted triangular cat perches/beds in the corners, and then a sisselled climbing post at the other end on the far wall. Having two cats in a very small space, and since we were in a pretty urban environment they were INDOOR cats only, could have been stressful on all of us, (those of you who have ever experienced dominance struggles among the feline kind know what I'm talking about. Some smells NEVER go away), but the cat walk really helped them out.
Now whether or not it could be considered a TOY is up for debate.
The only cat toy any of my cats have any interest in, (now that they have discovered the joys of disemboweling living creatures like birds and small mammals and in Maya's case, insects), is a large catnip cigar. They ALL love this toy, and it frequently ends up in the living room or in some other dog space. After a few object lessons as puppies, both dogs ignore it as beneath their notice. And since the smell is pretty pungent, the dogs know it exactly as a toy they are not supposed to touch.
We did lose a few of those fur-covered mice to puppy teeth when Nanook first came home, but because we were constantly with him, he never swallowed one.