Hi SScott,
I still know of no commercial product. I finally secured a small metal ring tightly to the computer double slot via a nylon zip tie (through side slot, out the bottom slot, through ring and zip tie fastener--draw tight). I had a metal cable with loops on both ends. I loop the cable around a table leg and attach it to the ring with a small combination lock. The week point is the zip tie, but it is so firmly attached that it does not leave much room for someone to cut it quickly or easily. Sofar my computer has always remained on the library table when I go for coffee. Certainly not the best solution, but for now it seems to work. I wish there were a better solution. Please let me know if you find one. Ron