I really, *really* liked my late 1970's-era 6809 system. 64k of RAM, custom graphics and sound cards of my design, timers, serial port, multiple floppies. I thought it was getting old in the tooth (it wasn't, it still works, should have had more faith I suppose), so I wrote an emulator for it -- the entire system, hardware, software, a front panel (which the original didn't even have) everything. Still works great, but due to the increase in CPU power over the years, the emulator is one heck of a lot faster than the original hardware. You can use it too, if you're so inclined and you're running some version of Windows, XP or later (might still work under Windows 95 and/or 98 for that matter.) Includes various compilers (Dugger's c compiler, for instance), forth, assembler, cross-assemblers, linkers, basics, some arcade video games that used the graphics hardware, and probably the vast majority of the commands that were available for the DOS, which was FLEX09. Percom PSYMON monitor. If you ever wanted to play in a nice, safe assembler sandbox, it doesn't get any better than the 6809. It just gets faster and wider.
For linux, the answer is Midnight Commander. Between the very nice editor and the dual-pane do-lots-of-things text mode interface, it's still my go-to under linux, I even use it on the Mac. Thankfully, they've kept it reasonably up to date, although making a native mac version without inflicting a much broader *nix ports package on the system is a real pain in the butt.
For the Mac, I use both of the above, MC natively and my emulator under a VM running a network-isolated XP, and I still run a PPC version of my HP-48G, which, I'm afraid, has made any other calculator use not only pointless, but nearly impossible. I also have two of these calculators in hardware, both of which still work fine. Because Apple dropped PPC support at OSX 10.7, my daily driver machine still runs OSX 10.6 and is likely to continue to do so unless I can find a native version of the HP emulator for Mavericks. When I decided to move past OSX 10.6 (Mavericks is actually quite nice, finally), I bought a new machine and plopped it down in my ham shack.
Ham radio: Easy. My Palomar loop antenna. This tiny (about a cubic foot) antenna system has pluggable loops for 150-500 khz, 500-1700 khz, 1700-4000 khz, and 4000-15000 khz. I like to drag it out into the unimproved areas a few tens of miles from here where there are zero power lines, telephone cables carrying data, neon and other signage, plasma TVs, buildings and so on, and enjoy amazingly good, noise-free SW and amateur radio reception on the radio in my truck without having to set up a physically large and cumbersome antenna. I also have a Panasonic RF-2200 portable analog radio that I take on trips. Both of these are pretty old, tech-wise, but both remain in regular use and have stood the test of time very well indeed.
Music: A Marantz 2325 stereo receiver and a pair of Marantz HD-880 speakers. Not only does this setup sound nothing less than awesome, it eliminates the tedious menu surfing that more modern gear forces upon us. Everything's on a front panel knob. Everything. I have (very) modern gear in the home theater, but in my office, the old Marantz blue face remains king.
Lastly, I still have, and continue to play, a 1950's Fender Stratocaster guitar. I have a fair collection of more modern guitars, but the strat's neck is still the best of all of them. Luckily, for most of my life I've been a casual enough musician, and have spent enough time on other guitars, that I've not had to have the thing re-fretted. I don't look forward to that. I can't imagine it'll be the same. Of all the old stuff I have, this is the thing that has not only kept its value, but appreciated far beyond any dollar figure I could ever have anticipated. Not selling it, though. Ever. :)