is a printer's ruler--you know, the kind that has picas, inches and points. It's a metal ruler, (ours were) about a foot long, and has a "T" on one end, shaped like a dome. Wonderful, compact things, and great for cutting as well. It was the sort of thing I carried in my pants pocket when working in a print shop. Great when doing paste-up, as well as on the press, measuring margins, etc.

Duh, should have checked eBay! Here is what I'm talking about. Can't beat them! And I heartily recommend them for DIYPlanners, too...

-Jon

[edited 28Mar07 by Sara: minor link adjustment]