Computer hardware

The following is my hardware shopping list, more or less. Observations and rants are included.

Workstation

CPU
(Low-end) Intel Xeon processors are generally nice and suitable for a workstation: ECC memory support, fine TDP, and all the perks of being mainstream. Of course there are security vulnerabilities, potential backdoors, vulnerabilities in backdoors, and numerous backwards compatibility warts, but there are comparable ones in other affordable and suitable for common computing tasks CPUs. Though as of 2019, it seems that AMD CPUs may be a generally better option: ECC is not disabled even in Ryzen (desktop) CPUs, and they seem to beat Intel in benchmarks/specifications at the same price.
Memory
Software keeps eating all the available memory, and even if one manages to avoid memory hogs, it's still nice to cache more. So it's usually a good idea to have plenty of memory (either maximum supported by CPU and motherboard, or at least aiming upgrades to a maximum size). Kingston seems to be relatively reliable and produces ECC memory; Crucial and SuperMicro seem fine too; personally I've only had issues with Corsair (which makes non-ECC memory anyway).
Storage
Probably it's the time to move to SSDs, but I'm still using HDDs. There are reliability statistics around (usually it is, from least reliable to most: Seagate, WD, Hitachi and Toshiba, which is also reflected in prices); it's hard to deduce reliability by a vendor, but WD Red disks work fine for me. RAID and/or backups are nice to have anyway.
Graphics card
Some CPUs (even workstation ones) have integrated graphics, though even if it's present, it may be used just as a backup. As for discrete video cards, the primary issue for me is software support (both drivers and higher-level software such as X compositors). Both AMD/ATI and Nvidia are problematic, and the issues seem to vary from model to model, so the safest way may be to ask around about compatibility of modern models with the software one plans to use (and perhaps exact version of it, including kernel/drivers: h-node.org listing alone doesn't guarantee that things will work any smoothly), and possibly with libre drivers. Although AMD seems to be generally more open and friendly to software as of 2019. As with motherboards, generally ASUS wraps them nicely, though it's better to check reviews and benchmarks instead of brands.
Motherboard
ASUS workstation motherboards seem to be fine, and usually there is a few to choose from. Non-workstation ones tend to come with Wi-Fi, LEDs, and other things one may prefer to not have. Though generally it's better to check reviews and benchmarks for motherboars on a chosen chipset at the time of buying.
CPU heat sinks and fans
Noctua is nice. Painless CPU mounting is great, it's silent, and cools CPUs well. Newer AMD stock coolers are not so bad either (except for LEDs), though still behind Noctua.
Power supply
Since a PSU malfunction can fry a motherboard and components on it, it may be a good idea to get a nice one, which would easily handle the used hardware. "80 Plus" ratings can be consulted, and Thermaltake PSUs are not the worst, though their newer models are covered in gaudy LEDs.
Chassis
Full-tower metal cases are good for building and for cooling, and often come with handy features that are less common on smaller cases (e.g., front panel ports for SATA HDDs and other I/O, large/slow/silent fans), though tend to be heavy. Thermaltake ones are fine, NZXT looks nice too. Unfortunately annoying and ugly LEDs are common on full-towers. Maybe smaller and lighter cases would be fine too.
UPS
APC seems to be fine (except for its software, which is awful, as usual for software shipped by hardware vendors, but it's usable without that software). An RBC7 battery lasts for about 3-5 years (and it's recommended to change them every 3 years), though it's a pain to recycle one properly.
Keyboard
The "Truly Ergonomic" keyboard has a relatively nice layout, though custom keyboards may suit one better (and are fun to build). Split keyboards seem nice too, but I haven't tried them yet.
Mouse
Gaming hardware tends to be unreliable, but mice advertised as gaming ones tend to be handy. Logitech mice seem to live longer than others (and particularly than those made by gaming companies).
Home router
So far I had D-Link and ASUS routers that died, Linksys that lived until it got outdated, and TP-Link router that lives, though it's not much of data points. LibreCMC and OpenWRT maintain supported hardware lists, which are handy for choosing from. OpenWRT seems to be better at supporting router models long-term, while LibreCMC would drop support even for once-supported ones (not to mention supporting much fewer models in the first place).

Generally it's a good idea to look up the models on websites of vendors in order to get accurate and complete specifications, though it doesn't guarantee availability in local stores, and may take a few iterations. As of 2019, tech companies didn't adopt structured/machine-readable data exchange/publishing, so hardware search/picking services tend to provide and use incomplete information. Though they still may be easier to get information from, since official websites tend to be infested with JS and marketing. I've considered composing a table with various vendors, indicating whether they cover hardware in LEDs, make websites unusable and drivers hard to download, etc, but it's basically as bad as it gets for every major vendor.

Media/gaming/entertainment centre

A basic setup can be quite similar to that of a workstation: a computer, a screen, speakers, some input devices. The major issues are content retrieval and manipulation (documented separately, in the Home entertainment centre note), and awkward hardware (documented below).

A computer

It's much easier to give up on workstation priorities (such as ECC memory and not having gaudy LEDs), since there's plenty of compromises to be made even then. In the end of 2019, I went for a build with Ryzen 7 3700X (because of a relatively low TDP, and a stock cooler), ASUS TUF GAMING X570-PLUS (WI-FI), HX432C16PB3K2/32 memory (which seemed a bit strange, with my workstation from 2012 also having 32 GiB, though this memory is faster), GV-R57XTGAMING OC-8GD graphics card, Corsair HX750 PSU, a couple of NVMe SSDs, and just a voltage stabilizer instead of an UPS. Finally tried an NZXT case (H710); it's indeed quite nice, though heavy for a mid-tower.

Input devices

The Xbox One controller works easily with MS Windows 10 over Bluetooth (though the batteries only lasted for 40 hours of gaming, and one has to select "mice, keyboards, etc" when adding a device, despite MS Windows suggesting to pick a separate option for Xbox controllers) and over an USB cable (micro-usb). For some reason (which I have no idea how to debug with a reasonable effort, and likely it would violate long and unreadable game licenses) games lag when it vibrates, but disabling vibration gets rid of the lags.

A screen

OLED matrices seem to be used relatively commonly for media-oriented "TVs", but modern "TVs" are monitors with built-in computers, loaded with proprietary software, malware, and even advertisements (see also: HN thread discussing spyware on smart TVs). Apparently there are similar screens marketed as "conference room" or "commercial" ones, and perhaps non-OLED can be fine too. With comparable specifications, regular screens seem to be quite a bit more expensive than TVs; possibly that's because TVs can feature frame interpolation and double frame rate in their specifications, and/or advertise resolutions with interlacing. Though it's commonly suggested that preinstalled spyware and adware lead to lower prices as well.

I went for a gaming LG screen (32GK850F-B, VA matrix) in 2019, which seems rather nice and not particularly expensive.

Old cable television

While OTT services may make more sense these days, one may want to preserve regular TV (such as DVB-C). There are receivers that can output video over HDMI and sound separately (e.g., over RCA), as well as speakers with dual inputs (e.g., also RCA), and computer screens commonly support multiple inputs, so that both DVB-C receiver and a computer can be connected to both a screen and speakers (so that TV can function independently of a computer). There are PCI and USB TV tuners too, but according to comments on the Internet their quality is very low (both hardware and software), so solving it with additional wires seems like a better option.