Largely as an experiment, I hooked up my basement computer to my 55-inch UHDTV and set Windows to its native resolution of 3840x2160.  My first impression was "this is way too large to be practical as a computer monitor".  But then a curious thing happened: I found I stopped maximizing windows--a habit not even 1080p displays could shake me of.  I always felt desktop systems with free-moving windows were pointless, as all the practical workflows I've ever seen involved either a single maximized window, or in a pinch, sometimes with two side-by-side (which Snap makes into child's play).

At 4K/2160p, my typical desktop instead tends to look something like this (external link because this is absolutely ginormous and will break the page otherwise):
http://i.imgur.com/mg774GO.jpg

The application I'm primarily working with at the time goes to the bottom center, right in line with my seat, while ancillary stuff goes off to the sides or top, where it's more difficult to reach--ergonomically speaking--but (and here's the important part!) still completely visible at all times.  Which alleviates a lot of the pain of having to Alt+Tab between maximized applications when, for example, transcribing data.

That's really cool, and really useful for a development workflow!

I'm personally still going with a 1080p screen next though, but that has more to do with me wanting to get one of those high refresh rate ones for games.

Yeah, that's the one downside to running at 4K--due to HDMI bandwidth limitations, you're limited to 30Hz refresh, which is painful at times and not at all feasible for gaming.  I also had to patch my Catalyst drivers because for some reason the driver caps the pixel clock such that you can't hit anything above 1080p.

Oh, lol, I see the string of emulators at the top.

4K display I guess will also remove the hassle of using two displays by pooling all your apps in one easy to reach area. Sure, two 1080p monitors would be a great alternative, but you'd still be limited to apps at two at a time.

But, it's a tradeoff. Let's see if that 30Hz gets in the way or not, let's see how long you'll last.

Hmm, I may want to try a 4k then. I tend to leave windows unmaximized fairly often, so that may fit my workflow well.

I cannot really discern 30 hertz refresh from 60 hertz (or even 75 hertz, as most of my hardware is running now). So I might not even have noticed that if it wasn't mentioned.

Try playing a game at 30Hz - you'll notice the difference immediately.  For a 3D game it might not be so bad because those tend to be designed to remain playable even in the presence of lag, but anything requiring more precise control (say, old NES games, or retro stuff) is nearly unplayable.

The laggy mouse cursor movement and scrolling does induce eye strain as well, even when you don't consciously notice the effects.

By the way, you see that DBZ video in the top right corner?  For a sense of scale here, that's a 1080p video - with the window sized to the video resolution.

By the way, you see that DBZ video in the top right corner?  For a sense of scale here, that's a 1080p video - with the window sized to the video resolution.

Damn, that's a good sense of scale. Crazy! I think it'd be too big for me. I mean if I were sitting a ways back I'd have to quint to read text. I'd have to program at much larger fonts. It'd just be... weird I guess.

Wow, that is one big screen.

I do think I will stick with my tripe screen setup I like my screens clean, and 3 fullscreen apps on display at all times does that for me.

Yeah, it's a cheap Element set from Target that I got for $400 on Black Friday, it actually surprised me how good the picture is at 4K (this is another reason I hooked the PC up, to ensure the TV's native res really was 4K - some cheap sets accept 4K input but only display at 1080).  The backlighting is a bit uneven, though, there's a brighter "border" around the edges, only really noticeable with a very dark screen.

Triple screens would be nice too, but my OCD would force the three monitors to be identical (with identical resolution), so I would have to buy all three at the same time.

Oh, and the icing on the cake is that the PC now doubles as a 4K-upscaling Blu-ray player.