Are dot matrix printers still used anywhere?
Solution 1:
As old as it is, it is still used quite a lot. As Hofa mentioned (Carbon Paper), some of the examples that I've still seen:
Packaging Slip that is glued on the box. You sign on the slip on the box, the courier remove 1 copy for himself (with original signature), and leave the carbon copy stuck on the box. (But recently lots of courier uses the PDA and you sign on the PDA which is horribly hard to get a nice signature)
Pay slip that I get from my employed on fortnightly basis is basically on a form that they print on the inside of the form. To see what is printed, we need to tear off the side, and unfold the form and then you can see the amount inside.
Bank / ATM Card PIN mailed out on similar paper to the payslip paper. (and it is even more secure because they blackened out the area where the PIN is printed to ensure you can't put it behind a light and see the inside)
Old order forms (Companies who still refuses to move to electronic billing / filing), they will use forms in du/tri/n-plicate, one for account, one for another department, and "yet more departments"
Solution 2:
Actually, they're still being sold too! There are even color dot matrix printers. They cost less to operate and seem to offer some additional functionality that you can't find on the more modern printers. (And you can easily re-ink them if need be.) They are highly durable too. The use of a continuous paper feed also makes them very useful for data logging. They are practical if printing quality isn't important. In general, people continue to use them for their extreme low costs per printed page.
Solution 3:
Dot matrix printers are surely still used, a lot actually. You just named the biggest market for those: carbon paper.
Solution 4:
We still use one in our office to print off anything that doesn't have to "look good". Timesheets, payroll reports, system logs, stuff like that. Besides the ribbons costing a fraction of having to replace toner and/or drums for the laser printers, our dot matrix can also print much faster, jam less often, and doesn't overheat if left running for a long time. And the continuous feed paper needs to be changed less frequently.
Most of these advantages disappear if you're not just printing draft quality text.