Why yes, that is an Apple Studio Display on my desk
Even up to the year 2000, most desktop computers were attached to a hulking great VDU (Visual Display Unit), a huge box of a thing that was usually deeper than it was wide, and that housed a heavy glass assembly called a Cathode Ray Tube.
These CRT displays were not just big and heavy, annexing proportions of your desk that would seem ludicrous now, but they drew an enormous amount of power; I remember reading detailed analyses of how a flat-panel display would pay for itself in a given number of years since it used so much less electricity.
What they weren't, though, was bad. It's easy to look at those ancient behemoths and assume they had terrible colors, that their convex, bulbous glass front distorted everything unpleasantly, and that because you don't get a perfect grid of pixels to light up, details were soft and fuzzy. Actually, when stand-alone flat-panel screens were introduced, it was common to dismiss them; compared to even a mid-priced CRT, they were small, expensive, and didn't display colors anywhere near well enough. For many years, image professionals wouldn't touch a flat-panel. Plus, they started life with analog connections, so that even though, yes, your Mac could be outputting a perfect grid of 1024×768 pixels to a display that had a 1024×768 panel, you had to fiddle with the settings to get the pixels to line up properly.
What's more, while most consumer CRTs over the technology's lifetime were indeed a little fishbowl'd, as flat-panels started taking over, CRTs with completely flat screens were becoming common.
You could also, for a while, buy screens that were flat on one axis; I know for sure because the first Apple monitor I bought was the AppleVision 1710 which had a Sony Trinitron tube. It was flat vertically but bowed laterally. This is also how I--and my poor dad--know for sure how heavy these CRTs were; this was the display I had connected up to my Macs while I was going to college, and it was dutifully lugged up and down flights of stairs to student accommodations at the start and end of each academic year.
Still, it was inevitable that flat-panels would take over, and in 1998 Apple introduced its first flat-screen monitor, the Apple Studio Display. Introduced at a time when Apple's Macs were still all beige, this magnificent vision of translucent blue and blue-grey plastic looked desperately modern and exciting. It would be rereleased in white and turquoise to match the Power Mac G3 which was introduced in 1999, and while that model comes up reasonably often on eBay, these original flat-panel Apple displays are a bit rarer.
"Flat"-panel might be stretching things a bit. Sure, the actual panel itself is flat, but turn this thing side-on, and the whole thing is anything but!
That's an 11-inch MacBook Air beside it. For comparison, the Apple Studio Display is nearly fourteen and a half times thicker than that entire computer--keyboard, trackpad, internals and display.
I don't really care, though; it's a beautiful thing, and I still use it. I've long been a staunch advocate of using two monitors with your Mac--one big, main display such as my old Samsung here, and a smaller, secondary monitor such as this 15-inch Apple Studio Display. I'd rather have two moderately-sized monitors than one huge one (especially since, without a utility such as Moom, the Mac's window management is so primitive) as it suits the way lots of us work: main focus on the primary display, research, Twitter, iTunes, email or whatever you like on the secondary. And actually, a little display works conceptually really well for this. Plug them in, arrange them in the Displays pane of System Preferences, and start shunting stuff you want to keep an eye on but don't want to focus on off to one side.
It's easy to use this old monitor with even the most up-to-date Mac Apple makes; all you need to do is to convert the old connection. Mine is one of the very original 'Rev. A' models, so I have to convert the old-style DB--15 connection (though its presence here means I can still use this with old Macs such as my LCs!) to VGA with an adapter off eBay--Rev. Bs were VGA out of the box--then convert that to Mini DisplayPort with a standard Apple adapter.
It looks a bit of a kludge, I know, but I actually really love that--that despite everything which has changed in the 16 years since this monitor was introduced, I can still easily Frankenstein together a solution to use it. Indeed, I've had it connected up to an iPad too--perfect since its screen exactly matches the pixel dimensions of the non-Retina iPads--and I love how my head spins thinking how, if I thought the Apple Studio Display was a pretty futuristic and exciting piece of hardware in 1998, quite how my mind would have been blown with the iPad!
If you'd like to pick up one of these old displays, get on eBay and pick one up along with the adapters you need. The white-and-clear Apple Studio Display LCD models are much more common, and so can be had for just a few bucks, but be careful--if you get a monitor such as these which use Apple's ADC standard (a precursor, in some ways, to Thunderbolt, which carried analog and digital video, USB and power along a single cable) then you have to factor in quite an expensive ADC to DVI adapter.
What was your favorite Apple display