I design and manufacture an electronic cigarette device that uses a 555 to PWM a MOSFET for variable power output. Super simple and robust but will be switching to MCUs soon for more features.

It's actually incredibly rare in consumer products. Especially since an 8-bit micro controller can cost much much less in bulk today.

Edit: and 8-bit micros come much cheaper than Digikey when you buy consumer product volumes directly.

Do you know what it is was used for in non-consumer products?

It's in a number of ancient DC time-delay relays.

BBC micro http://www.8bs.com/inbbc.htm

Cool! Will it be something on the web?

Personal project to start. See if it turns into something more.

I'm imagining something like 'reverse-dns' for electronic chips.

That is, today if you take apart a consumer device, you can can see what chips are in them and get the datasheets pretty easily (a 'Whois' lookup) - but there isn't an equivalent for looking at a chip and seeing which products it was used in ('reverse lookup'). I've done this successfully with a few radio modules but I wanted to start with something more iconic like the 555.

My question is if there is a product that exists solely because of the 555 just as the Texas Instruments Speak & Spell existed solely because of the TMC0280.