In some cases, it can still be worthwhile to buy ink, if certain circumstances are true: - You can get an inkjet printer for free (not difficult, people throw

In some cases, it can still be worthwhile to buy ink, if certain circumstances are true: - You can get an inkjet printer for free (not difficult, people throw working printers away all the time) - You can invest the money conservatively at a high, but not extraordinarily high rate - You print very rarely My current inkjet cartridge cost $50. I've had it for two years, and it's about 60% full according to the display on the printer (which, admittedly, might be lying). That's a savings of about $250 over buying a cheap laser printer. Assuming that the laser printer will last indefinitely with no further expenses (hey, it very well might), I need to get about a 1/5 ROI on the $250 over the expected lifetime of the ink (5 years, but assume the software lies and call it 4) to break even. That takes about a 4.7% interest rate. If you can invest the money and make about 5%, it's actually cheaper to buy the ink. I could do this, by "investing" it in paying student loans more quickly, so it makes sense. Of course, if you print a lot, it's absolutely silly to use an inkjet for it.