I was spending way to much time at my computer and my trackball arm was starting to ache at night because of it. I decided to create a device to angle my trackball so my arm could be in a more natural position while I "moused about". This is the result. The Logitech M570 trackball has a few underside features that allow it to be held in place from below. The battery cover plate must be removed to insert the unit into the holder. I also carved out a hole to store the plate so it doesn't get lost. :-) As I printed it, the unit fits snuggly into its place, to the point that I can even hold it upside down with out it falling out, but I wouldn't count on that. It stays put nicely in its cradle .

Plastic on desktop surfaces slides around a bit too much so you will probably want to add a rubber bottom (jar opener?) or a cloth which is what I use right now. Also the cloth can be folded to create a wrist-rest to add support for the hand. One could also secure high density foam, gel, or silicon material to the top surface as needed.

The space between the table "pad" and the trackball mount needed something to make it more interesting and improve the aesthetics. I've always been fond of MeshMixer's tree shaped support structures and decided to incorporate it into the design. I then stuck a few critters in among the trees. These are my sources.

Stanford Bunny (classic in 3d printing) by phooky
http://www.thingiverse.com/thing:3731

rabbit scan (very nice looking) by fred14000
http://www.thingiverse.com/thing:1171055

sitting fox (quite pretty) by slavikk
http://www.thingiverse.com/thing:934033

The blender file is a huge mess of objects involved in creating this. I'm including it in case one wants to do further remixes. If only printing is desired, just download the stl file.

If you like this and are feeling generous please consider feeding Foxpup. -> bitcoin:1KTAf3EM1kNWxpKrSSFqbESqYQZf2PAXdm Any amount, large or small, is appreciated, but only give if it brings you joy, not out of a sense of obligation. All the good ideas that Foxpup gets come from the Author of the universe and Foxpup is just passing them on :-)

2016-09-25
At the request of one user, I have provided a version with no trees or critters underneath, so the user can add whatever is desired. I strongly recommend putting something there to provide adequate strength. In that spirit, I also added a version with a simple support. It isn't pretty but it is functional. Lastly I put pass-through holes in all products (V2) where the trackball "stud" is. I did this to make it easer to pop out the ball for cleaning. The previous version is just fine and left in place as a reference, but I'd print V2 because of its improved utility.

I also added a low-poly version for those who would otherwise have trouble with the bitter gile.