Only a few of the very high end CRT's could be interfaced with a computer in a digital manner and it was mainly for the purpose of replacing the factory LUT.

If it was the monitor itself the one that triggered the screensaver on it's own without talking to the computer, well, it's perfectly possible, but I'd lying to you if I told you I recall ever reading or hearing anything about it.

Now if it's a CRT we're talking about, even if you managed to track the electron beam with a magic invisible memory mask, or profile the fluctuations of the deflection yoke or whatever it is that it could have been used to tell how much a triad has been used, then perhaps it would have been theoretically beneficial for someone too poor to afford a replacement monitor every 5-6 years or so, but that's just stretching it...

A flat panel will not wear out gradually (as far as you'll be able to notice on a regular situation, that is) as a CRT does, so the pixel either works or doesn't, but there's no telling when a pixel's going to die, so the whole thing just doesn't make any sense to me.

Jorpho wrote:

A long time ago I recall hearing about a monitor that would somehow record the usage of each pixel of the display, and then activate some kind of screensaver that would proportionately activate the least-used pixels more than the most-used pixels, thus ensuring even use of the entire display. I don't think this was a CRT, but some kind of flat-panel display (which doesn't really make sense now that I think about it, since flat panels don't decay that way, right?). It might have been for a laptop.

I was trying to search for this just now but didn't get anywhere. Does this ring a bell with anyone?

LCDs will not "wear" in this manner (like Lo Wang said, they will either work or not work), however emissive displays like CRTs and PDPs (Plasma) will. A lot of higher-end PDP TVs had an "anti-burn-in" feature that would "wash" the screen with various random patterns to prevent/minimize image retention. Usually this cycle was suggested to be run after playing videogames or anything else that draws a fixed UI on the screen for any extensive length of time, especially on early PDPs, as they're more susceptible to image retention than CRT displays.

Most likely, however, what you're thinking of would be something related to CRT projectors where the guns can end up with over-bight or over-dim spots if they're run frequently with letter/pillar-boxing or something else like that, and lighting the "unused" portions of the guns can help to alleviate that (it does, however, wear the entire thing as any power-on hours is wear).

My guess is a plasma display. CRTs are analog and it would be difficult to track the exact pixel being activated. LCDs don't wear out like that.
That pretty much leaves PDP

Plasmas and OLEDs both do auto-wear leveling between the three colors (RGB) as some colors age differently with that tech.

I don't think any of them track usage and adjust based on that though.