If I don't use my "tree house" concept, I could do something similar to this "ramp" with the cat barn to the side like this one. LOVE this too... just not as "blending" into living room space as a tree-looking one would.
Trixie Malaga Cat Tree in Anthracite-Petco. Pretty sure this is an absolute necessity. Because I'm a crazy cat lady.
Krabpaal Ankara Grijs
Make a magic carpet cat hammock for your kitty!
Majestic cat Products 73 inch Cream Bungalow Cat Furniture Condo House Scratcher Multi Level cat Activity Tree >>> See this great image : Cat Beds and Furniture
An incredibly large cat tower for your more active cat.