Linux

Even if the old mouse is the right choice, I was thinking that one kinda has to know that to know how much time/money one is gonna put into this. I mean, if the problem is "I want a cheap mouse and am not too particular about the specifics", you can get a new wireless optical mouse for $5. It's just not worth putting much time or money into getting an old one working; that kind of price seriously constrains the solutions you might be willing to do.

If one specifically strongly prefers a particular piece of hardware, they might be willing to put a lot of money and effort into getting the thing working. People have built new controller boards for buckling-spring IBM Model M keyboards. People have spent hundreds of dollars to get a Model M (or a modern remake) going in a modern environment, even though one can get a rubber dome keyboard for $6. They aren't doing it because they're unwilling to pay for a new keyboard, but rather because they very much want a piece of hardware that works the way it used to. For people like that, a new $5 mouse is not a reasonable option.

I've been on both sides of that equation.

I personally profoundly dislike "virtual buttons" on trackpads, despite the market generally shifting in that direction and them being somewhat cheaper. I am willing to limit myself to getting Lenovo Thinkpads, because they're one of the very few laptops out there that -- on some models -- have trackpads with (1) physical buttons and (2) the three physical buttons that Linux prefers. If I had to pay $100 to get a trackpad with three physical buttons on a given laptop, I would, though that's far more than what a "virtual button" trackpad would cost. Hell, I'd probably do $300.

On the other hand, I don't care much about mice. As long as it's got five buttons, a scroll wheel, and a USB connection, every mouse I've ever had has worked pretty much fine. I tend to just get whatever's cheapest on offer when I get a replacement mouse (my most recent mouse, a Razor, being an exception; my monitor refresh rate is now above the typical USB mouse polling rate of 125 Hz, and I wanted a mouse that would report position at something above my monitor refresh rate).

And I know that it'd be pretty hard to convince me otherwise on either point. Like, I've used expensive mice and cheap mice and they just haven't made much difference. On the other hand, I have used and very much dislike virtual trackpad buttons. So I wouldn't want to tell someone to go either route across-the-board without knowing where they're coming from on this.