Specifically, I got the Varidesk Pro Plus 36: http://www.amazon.com/VARIDESK-Plus-Height-Adjustable-Standi...
Had to watch for a few things: is the keyboard platform the same height as their monitor (ideally, no). Would monitor/keyboard/mice cables get crushed if you keep the desk down? Can it support two 24"+ monitors?
It's incredibly durable (it'd won't tip over short of putting your entire weight on it in the elevated position). Use it for 2-3 hours/day (with a compression mat I got from costco for $20).
There are a couple models, and none are that cheap ($300-$400), but I've had back pain and poor posture all my life so I figured I'd invest what is typically 1 month of my living expenses into this.
http://www.ikea.com/ca/en/catalog/products/S49022524/#/S5902...
We had existing desk tops so we just had someone come in and install the legs. They work well and given that we tend to average 4 27" monitors per person they handle the extra weight well. Mechanical riser's are awesome!
They also rise fairly high, important when you have someone who is 6'9" on your team:)
Just don't forget to buy a standing mat to, ummm, stand on.
http://thewirecutter.com/reviews/best-standing-desk-mat/
EDIT Yes, the mat really matters, we've had a few ergonomic experts in and their advice usually varies but they all agree on using a standing mat.
HUGE difference
Pro-tip, get the wheels; everything should be on wheels, makes all the difference.
[1] http://www.haworth.com/home/resources/design-tools/image-sea... [2] a reseller has one on amazon http://www.amazon.com/Haworth-Planes-Height-Adjustable-Desk/...
It's sturdy enough for my laptop and 2 monitors from my sit height (~25ish? inches) to my stand height (~46? inches). The cable tray was a bit difficult to fit a surge protector into but I eventually found one that worked. The top is a bit different from normal desks, but it feels fine to rest against and use my laser mouse sans mousepad.
Most of my coworkers have some variant of the Geek Desk.
after having tried simply raising a "regular" desk to standing a year or two ago. Standing all day didn't work for me, but the crank-up makes it so I can stand in the morning and then sit for the afternoon. FWIW I use it cranked nearly all the way up and I'm 6'0" -- it might not be tall enough for someone taller than that. The crank is easy to operate and fairly smooth.
It's got a large surface for keyboard, notebook, coffee, etc. The second tier comfortably fits two external monitors + laptop.
It's very quick to move up and down, and the keyboard tray and monitor are independent. Not much adjustibility on the monitors, but otherwise I have no complaints.
Cost me about $60. I polyurethaned a plywood top instead of buying an Ikea top. Plus I stacked some books as monitor stands.
The only problem is it's too big to fit through doors so it has to be disassembled to move.
And you can even make it yourself!
https://www.indiegogo.com/projects/ergo-world-s-first-smart-...
$299 for the DIY Kit.
$399 for a full desk.
$599 for the Smart Version.