A desk organizer I designed several years ago.  

Sized for a 80mm (3.15 inch) hole on a Fully Jarvis desk.  Has a nice fit, with little play.  Great for storing pens, Post-It notes, tools, and anything else you'd like close-to-hand.

Has three separate compartments measured at 90mm, 65mm, and 23mm in depth (two sides and middle).