There is no such thread yet (surprisingly).
How about a thread that will list pictures of worn out keyboards? There are people here who own ridiculous amount of keyboards, and also seen probably more keyboard pictures over internet than any other person.
The point of it, would be to see how durable most popular keyboards are, that could help in making decision what to buy for some people. There was a lot of brand new Filco keyboard photos, how about pictures after for example 2 years of heavy usage?
What is interesting, not only if signs disappear from keycaps, but also how textured plastic polishes and keycaps shine. Sure all of it depends on how often do we use keyboard, and probably on style of typing. Still i think it would be interesting database of pictures.
To start thread, i have googled extreme example:
A medical transcriptionist has been using the same keyboard for 8.5 years to the point where the keyboard began to deteriorate, appearing as if some keys have melted. The most frequently used keys have shown severe wear; most keys no longer show their labels. However, the keyboard, from NMB Technologies model RT2358TW, is still fully functional.
I didn't know you can actually scratch through the keycaps.