I've heard of original Apple I computers (sometimes no longer functional) auctioning off for $50,000 or more. Even clones are worth surprising big bucks, provided they're old and popular enough. Even more ancient machines (so primitive and gutless that only nerds would even call them computers) often auction off for even greater sums. There's a fair number of museums (both physical and electronic) dedicated to preserving and displaying such stuff.
I abandoned my last 486DX2-66 platform almost two decades ago, after deciding that it was just not worth keeping around for legacy gaming. Followed just a few years later by my last Pentium-MMX/233, then a few more years before saying goodbye to my last P4. Emulation through DOSBox or some VMware (in Windows or linux) is helluva lot easier and better than keeping obsolete platforms (and their obsolete MS-DOS or Win9x/XP configs) up and running. No more messing with finicky SoundBlaster/Ultrasound cards, mouse issues, IRQ nightmares, DOS memory management, MSDOS vs Win9x/XP multiboots, CONFIG.SYS and AUTOEXEC.BAT and .INI files and all the rest of that crap. Just set up the emulator with whatever legacy hardware you want to pretend you have, how fast (or how slow) you want it to run, and click your game's new launch icon, can't get much easier.
I do, however, sorely miss my old-style RS232 ports. New RS232 solutions just don't push out enough signal voltage to work directly with older (but not too old!) tech gear.