The following is a guest post from Funny about Money.

My printer, an HP Photosmart 2610, has been out of black ink for the past month. I’m only just getting around to trotting to the office supply store to buy a new inkjet cartridge. I’m doing so solely because a client asked me to sign a contract sent in PDF format, which will print only in black.

But I haven’t stopped using the printer. Assuredly not.

If you have a printer that uses separate cartridges for black, cyan, magenta, and yellow, you can extend the life of your black cartridge—and delay buying a new one when the black ink does run out—with a very simple strategy. Never print in black unless you have to.

The only documents I print in black are those that will go out of the house. And, thanks to e-mail, those are precious few. Snail-mail statements to clients and miscellaneous other correspondence get printed in black or dark gray. Anything else is run out of the printer in blue. I use the lighter color of blue that MS Word calls indigo. This is readable, and it’s perfectly fine for something that’s just going to get dropped in a file folder or used as notes and discarded. Most of your printouts come under these headings.

Otherwise, I try to avoid printing things altogether. Instead, I store documents electronically. Paycheck statements and banking documents, for example, can be downloaded as PDFs. Any Word document can also be saved as (or, in older versions, printed as) a PDF.

Given the way inkjet printers work, I suspect (but can’t prove) that the pale indigo shade lays down less ink on the paper than the printer would spray out to produce the darker blues. So I theorize that printing in a lighter color conserves ink. If that hypothesis is correct, then printing formal letters and business correspondence in 80% gray type would extend the life of your black cartridge and be readable—even classy-looking, with a smartly designed letterhead. For example, my letterhead prints in black, but the body type is all 80% gray. The effect is very highly acceptable.

Using indigo blue for casual printing and black or dark gray for business documents can double the time between cartridge purchases or refills, depending on your printer use patterns.

Related articles at Funny about Money:
How to Buy Your Next Car in Cash
DIY Veterinary: The Dog-proof Hot Spot Bandage
A Couple of Small Household Hints

Crystal’s Questions:
Do you have any frugal printer tips?  How about any other frugal tips for around the house?