The SmartMark Tape Measure Accessory from SMC magnifies and marks. This $5 magnifier from their Master Mind Tools line attaches to any standard 1″ tape and makes a pinpoint mark by pushing it down when you’re at the desired length.
There’s even a video — I guess for those unclear on the concept. The SmartMark is a little more complicated than a pencil, but, for some of us who are approaching old fartage and still haven’t gotten used to the damned bifocals, it just might help.
SMC [Manufacturer’s Site]