In my best Hackaday voice...

If you do not have a prepubescent daughter then Glimmies may have slipped by without notice. A Glimmies toy is a small (about 80mm tall) anthropomorphic animal like toy that comes in colorful choices such as red, green, blue, yellow, pink or orange. However if you do know someone of the younger persuasion or have friends that just will not leave their childhood behind then you may have already discovered the joy of optical inverters that are Glimmies.  Within the belly of each Glimmies is a single LED and upon their head is an inverting photo-transistor.  When the photo-transistor is exposed to light shuts the LED in their belly shuts off.  At around USD $3.30 each they are probably not the most expensive inverter on the market but they maybe the physically largest.  However since you would need five Glimmies to make a single NAND gate this would push the cost of a single gate to $16.30.  Its probably not to much of a stretch to think that you could probably get a better deal if you wanted to buy eighty thousand to build your own colorful 8-bit computer (with built in LED display of course).