This isn't a weird UI as such, but it's probably a technology that isn't explored enough. Back in the very early 2000s before Javascript was universally available, we wrote a CGI-based technology that worked by persisting the entire state of the page between clicks. It was a true widget-based server-side GUI, so you could build single page UIs by composing widgets such as buttons, labels, and more complex things, hierarchically (like native GUIs). The whole page would reload between clicks but everything was so lightweight and tiny that wasn't actually much of a problem, at least by the standards of the day.<p>It's all open source but probably doesn't compile on modern machines, and of course for extra fun we wrote the entire stack including the webserver, CGIs, cooperative threading, database layer and C libraries from scratch. From top to bottom this is the entire stack:<p><a href="http://git.annexia.org/?p=monolith.git;a=summary" rel="nofollow">http://git.annexia.org/?p=monolith.git;a=summary</a><p><a href="http://git.annexia.org/?p=rws.git;a=summary" rel="nofollow">http://git.annexia.org/?p=rws.git;a=summary</a><p><a href="http://git.annexia.org/?p=pthrlib.git;a=summary" rel="nofollow">http://git.annexia.org/?p=pthrlib.git;a=summary</a><p><a href="http://git.annexia.org/?p=c2lib.git;a=summary" rel="nofollow">http://git.annexia.org/?p=c2lib.git;a=summary</a><p>Edit: I should say that it's obsolete if you can make the nowadays reasonable assumption that Javascript can be used on the client side. It's more like "this is the crazy shit that a team of developers in their 20s with VC funding, disfunctional management and time on their hands get up to".<p>Edit 2: It was used in production for quite a long time, certainly until the 2010s. If you were in a UK school in the mid 2000s there's a chance you might have used this.