Yes, a number of them (I believe I am currently on #5, as I have frequently had to leave them behind when moving), but alas I have no pics. (I will try to take pics of the current one for you, though)
Things I have learned about building cat trees:
1) they need to be TALL. Even just for scratching, most of my cats have made the most use of the portion between about 2'-4' above the floor, and of course they like to climb much higher. The last 3 versions have been basically floor-to-ceiling.
2) they need to be STABLE. This is awful hard to achieve along with #1 unless you have the thing screwed to the wall and/or floor (preferably "and"). Screwed into a *stud*, not drywall. I like an arrangement where the vertical part that is nearest the wall is about 8" away from the wall, and attached to the wall by means of a high-up shelf (cat tree - shelf - wall, you know?)
3) whatever you coat them with will get trashed a lot faster than you think, so do not be gluing it on. I have made some with carpeting scraps (the loop kind, not cut pile), some with carpeting turned inside out so they are using the burlap-y backing, and some with sisal rope wound around the tree. Each has its merits; none lasts nearly as long as you want it to. Sisal can be wound on VERY VERY TIGHTLY. Carpet can be stapled (hammer-in upholstry or poultry staples) but I've had problems with cats working the staples loose and getting mildly injured so with carpet my preference has become the following: bend carpeting around 'tree' portion very very tightly by hand, lash it on with strong thin string so it is as tight against the 'tree' as you can get it, then screw through a 1x3 batten laid over top the seam, so some screws go thru one edge of the carpet and some thru the other. Use long, aggressive screws, and clamp the batten on so it goes on *tightly*. Then remove the string (it was just there to hold the carpeting in place til you screwed the batten thru). This is a bit of a pain in the neck but is the best compromise I've found between holding the carpet on tightly while still having it be easily replaceable when it gets too ripped or hairy.
Good luck, have fun,
Pat, will try to get pics tomorrow
