I think my approach has been a hybrid of already mentioned strategies. One that I find particularly relaxing sometimes is salvaging....
/-- snip --/
Is it really worth scrounging things like an 8050 transistor or 817 opto when those items are readily avail from a legit distributor (LCSC) for a few cents each (S8050 = 1.6c/ea, 817 2.9c/ea and that's in 10 lot).
Keeping an old board and if you don't have the component doing a quick scrounge makes sense, but pulling apart everything in advance?? (I admit I did this when I was a young teenager, but at that point parts were 10x the price). Back in 1979 a BC107 tranistor was 15p (UK), now I can buy them for 1/10th of that price and that's not adjusting for inflation.
I still favor this approach as a complement for parts accrual, BUT, with certain qualifications.
IOW you raise some good points. In fact, I looked up the motors and, sure enough, you can get them new for ~$1-2 US$. The memory bios chip was a surprising plus, but still probably only a buck or two. I already have a few of those IR sensors (1838 type) and so on. I have at least 25 opto's, none are 4-pin though (all older 6/8 pin - many salvaged and some high-gain darlington types that I bought). Optos are easy to test for suitability in my own projects. The switches probably will get used at some point. The cables and connectors *might* be useful - it is infuriating to need one and have little choice but to have to order it and wait.
There was plenty of stuff that I left alone (most of the power supply components).
Here are the general rules that I practice.
I will not give in to the compulsion to scavenge everything possible (I have to admit that if it was a small board, I might have at one time, removed, everything removable).
I no longer bother with scavenging the item, if it is fried or I have good reason to believe it is fried unless there are some specific things that I need AND can test out. An example is an old discarded radio that I scavenged for only the ferrite coil antenna and the telescoping antenna (both are in use right now). When I opened it up, it was clear that at least one capacitor had leaked. I don't want inexpensive components that may be flaky, even to play with.
I don't (no longer bother with) scavenging the item for simple resistors and capacitors with very short leads. If that is all you can get, I understand and will not criticize.
I do scavenge nuts and bolts. I frequently search for small hardware like those and I can sort them in a bin as they are being removed (in contrast to dumping a large jar and trying to find the right ones).
Finally, I have to be in the right mood to scavenge and when I am, it is a relaxing activity. I have a hot air station and it is a little game (some kind of skill there) to remove items easily. I reduce the junk pile and add to the component pile.
That's my story and I am sticking to it
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