HDTVs have an aspect ratio, the proportion between width and height, of 16:9. This, more noticeably rectangular, format was seen as a suitable compromise between 4:3 tradition and the many widths of theatrical releases. Computers, high resolution since the 90s (give-or-take) to fit more stuff on screen, first adopted many HD innovations.
Widescreen, however, was firmly resisted. Internet video was not popular or even known to the general public. Vista, with its sidebar optimizations, was expected to make 16:10 tolerable. 16:9 was too wide to even be considered an effective option for documents and websites.
I must say: I don't know how I'd live without Sidebar making my monitor feel wastefully narrow and…
Now that the public is comfortable with 16:9, because at some point it ceased to be scary for display manufacturers, some are experimenting with even wider niches. 2560×1080 has about a third more width than a "FullHD" panel to add another side-by-side-by-side document to edit or snapped website to refer to. At this point, if people want to buy it, do it.
LG, at IFA 2013, unveiled their V960 all-in-one (AIO) desktop. This computer is housed inside a 29" 21:9 (technically 64:27, but those numbers are big and scary) IPS display. Despite lacking a touchscreen, and despite OSX screenshots for its also announced plain monitors in its promo image, the AIO comes with Windows 8 pre-installed. It houses a mobile GeForce GT 640M GPU and… well that is about all we know of its internals.
The company believes that you might use some screen width for picture-in-picture TV browsing. LG is not too clear on what functionality will be available to the V960. Other monitors in the line contain a TV tuner, but they never specified whether the AIO would have a tuner or just an HDMI input. Also unclear, whether video inputs are accessible to the computer for DVR functionality or whether it is delivered straight to the display.
The LG V960 was on display at IFA 2013. No pricing and availability information has been announced by LG.