Everyday Lean: Printer Toner
Rather than giving a late “toner low” notice that says the toner will run out (usually right as print quality degrades significantly), this printer gives specific notice, that you have 1000 pages worth of toner left, that you should order more.
It would be even more slick if the printer knew how many pages you printed per day and could say, if you printed 100 pages per day, that you have “10 days of toner left.” The signal to order more could be based off of days remaining — if it takes 5 days, worst case, to order more toner online, it could signal you then.
I believe Dell printers (built by Lexmark, it's not the famous Dell build-to-order model) will automatically take you to the online ordering page. Now if it could just automatically order the toner for you (via a pre-approved account), that might be nice.
Is it really worth all of that effort? No, not if you just followed a “two bin” kanban system and always had one toner in the printer and a 2nd on the shelf. That way, you just order a new 2nd toner when the one in the printer is empty. That doesn't require fancy software or display screens.