There is a product called Noligraph that is a plastic holder for five metal mini-pen refills in a line. It enables you to quickly make staff lines for adding annotations to a music book, for example. As far as I could determine, this product is available only in Europe and costs about 8 Euros ($10-$11), plus shipping--and they wanted much more than 10 Euros for that, too.
There's an interesting collector on line who home-made one of these things using the same type of short, metal, mini-pen refills that Noligraph uses, but sandwiched between pieces of cardboard. (
http://pencilsandmusic.wordpress.com...f-staff-liner/) He gave me the idea for one that I just made from long, thin, plastic, regular-sized refills instead of short, metal, mini-pen refills.
As drawn with the pen I made, the distance from the top line to the bottom line is exactly 0.5 inches (12.7mm). Noligraph makes a major point of how they set the five pen points in their holder precisely even, so I thought it might be difficult to get the tips lined up perfectly so they'd all contact the paper evenly. That turned out to be a non-problem because my refills are long, clear, plastic tubes and they flex a bit. So when you hold the thing at about a 45-degree angle and draw it along a straight edge with a little downward thumb pressure, the five lines come out perfectly, even when the tips are not perfectly lined up.
I also thought it might be hard to tape them tight together to the cardboard, but that was another non-problem. I didn’t use cardboard at all–-I just lined up the five refills with one thumb and forefinger while I wrapped them with cellophane tape. Surprisingly, they stayed in line. With several of these tapes wrapped around the five refills, they were held very firmly in line without any cardboard. (I did use thin cardboard to make a crude sheath for the thing, though.) When using this tool, it's a good idea to scruffle it around a bit on a piece of scratch paper just before you draw your staff lines in order to remove any ink globules that might be on the pen tips.
A tip on the refills: I found that buying whole pens at $9 for a box of twelve was cheaper than buying the refills. I bought a box of Pentel R.S.V.P. 0.7mm fine-point pens with black ink and removed the refills. Amazon has these pens, and they qualify for “FREE Super Saver Shipping.” The Noligraph looks nice, but good luck getting it from Europe, and it’s expensive with even more expensive shipping. Each of my home-made music staff pens is costing me $3.75 USD, and mine must have nearly twice as much ink.
The two photos below show the home-made pen. See how the pen is flexed while in use. I've exagerated it a bit here for the photo, but the flex is important so that all five pen points will contact the paper, even if the points are are not perfectly-evenly aligned.
