I know you have one, you cutting-edge bastard.
My interest: I’m tall. Regular desks and/or chairs require modification.
OMG, I had a tall desk once and loved it!
Built it myself from plywood and shelving- more of a workbench than a desk, but still.
It was the right height for standing work, and I had a barstool the right height for sitting at it too.
Man, my back is tingling with the need to make another one…
We have sit/stand stations at work, and we’re *supposed *to use them for a third of our day. I don’t, but I do like having the option of standing and use it if my lower back is bugging me or if I have been sitting at my dest for more then a couple of hours (usually I move around/go to other people’s offices). It helps quite a bit. The only recommendation I have is to make sure you aren’t standing on a really hard surface. That can bother the back as well. Also, I take my shoes off when I’m standing.
We have several people at work who built their own–usually for half their work station. They absolutely love having the option to move their lap top up high and stand while doing e-mail, etc.
This made me smile. You only wear shoes when you don’t actually need them to protect your feet from the ground. Out of context, that would be really silly.
As for our 6’8" OP, are you interested in actually standing at one? Because I’m only 6’2" and I notice that most of them are just a slight bit too short. Then again, I’ve never had my own, just used someone else’s.
I’m absolutely interested in standing at one…as long as it is the right size.
I call mine a “cash register.”
We have these Steelcase Airtouch desks at work. They go up and down.
I like them. They’re a lot more practical than the electrically-adjustable models I’ve seen, though it would be nice if they had a little more range. (I’m 5’10" and the highest setting seems like a tad too low - I want about another half inch out of the thing. (That’s what she said.))
I spend most of my day sitting but maybe half an hour to an hour standing at it.
One useful feature is that raising the desk makes it much easier to plug and unplug my laptop without banging my head. 
I have an adjustable desk at work. Since the day I got it, I’ve never had it in the sitting position. I stand all day except when sitting in meetings.
I have an adjustable sitting-standing workstation like this: http://www.amazon.com/Ergotron-WorkFit-S-33-341-200-Sit-Stand-Workstation/dp/B003Y3PF6E?tag=s601000020-20. I love it, I usually stand 15 minutes out of every hour, or anytime my butt starts feeling numb. 
I get varied reactions from co-workers, from people who don’t understand how I would get tired of sitting (
), to people who like it so much they want to order their own.
We have the adjustable stations too, which are cool.
What is NOT cool, is the software they installed on our computers. If you’re on your computer for more than thirty minutes, a little pop up video comes on and tells you it’s time to do your hand stretches. (You then follow along with the girl in the video doing the stretches.) annoying!!
As long as the lowest setting is not too high, try putting some small pieces of plywood under each foot.
My work space is a standing worktable. It’s 10ft. by 12ft. at 38in. and covered in carpet. If I want to sit I hop up on the table. But that a great way to get glass splinters in my ass.
I don’t have a stand-up desk, but I have a bookcase that’s just the right height. I keep it clear on top so that I can use it as a stand-up desk when sitting at my regular desk has me feeling achy, or when I just want to get my circulation going a little better.
Beware: Working at a stand-up desk might lead to serious errors in judgment. See the next-to-last paragraph here: USATODAY.com - Rumsfeld OK'd harsh treatment
We have the same thing: Workpace. Ours is a ten second break every five minutes and a five minute stretch break every hour or so, based on how much you’re typing or mousing.
in case anyone is wondering why you would stand up instead of sitting
Well, I’m going to figure out a way to rig up something. There’s no way I can get one purchased for me, so it will be a combination of blocks under the feet of my desk and perhaps a tabletop podium.
I assume that the proper height for the monitor would looking straight ahead or perhaps slightly upward, to encourage good posture?
I have the sit/stand desk as well. Cool thing about it is the option to save up to three height settings in memory. I also have two 30" monitors that adjust separately. According to the experts at this sort of thing, the correct viewing angle is slightly looking down. We have the Workpace software as well to enforce breaks although it can be annoying when halts work in the middle of something.
Desk needs a cup holder though.
Churchill used a standing desk sometimes, too: http://nextdesks.com/blog/wp-content/uploads/2012/11/churchill.jpg
