I purchased a laser printer a long time ago. I think I bought it back in 2007, and since then, it's felt like a good investment. The printer was cheap, it prints quickly, and I've only had to buy new toner for it every once in a while.
I recently discovered that if I hit the "GO" button on my printer, a Brother HL-2040, then it would printer out a diagnostics page listing the number of pages printed, the number of times the toner was replaced, and the number of times the drum was replaced.
Being an engineer, I was instantly interested in these numbers. How much had I spent on toner? How much did it cost me, per page, over the life of the printer? Well, given the numbers on that page and a little bit of pricing research, I can figure all of that out.
According to my printer's diagnostic page, I replaced the drum once, the toner 3 times, and printed 7475 pages. I think the printer cost about $80 when I bought it, a new drum costs about $88 right now, a new toner cartridge costs about $49, and 1500 sheets of paper is $15. All told, I've spent $315 on the printer, toner, and drum and about $75 on paper.
In total, I spent $390 or about 5.2¢ per page.
Unfortunately, my super reliable HL-2040 is no longer being sold by Brother. If you'd like to get a similar printer, I highly recommend the HL-2300D. It's got a number of improvements over the HL-2040 that I've been coveting: duplex printing (the ability to print on both sides of a page) and a high-yield toner cartridge option that is a bit more economical. In terms of toner alone, the high-yield toner costs about 1.8¢ per page ($46 / 2600 pages) and the regular toner cartridge costs about 2.6¢ per page ($31 / 1200 pages).