I used a standing desk for about 6 months, one with comfort matting. I didn't notice a difference. I also think standing desks don't offer any health benefits over sitting. I can state my reasons why if there is any interest.

I got some great standing shoes (normally for nurses chefs), and a standing mat (normally for kitchens and workshops). Once i had both, I could stand all day and have no fatigue.

I've been standing for about 18 months now, and I've lost weight, and have much more endurance and energy playing with my kids.

I'm not, but I have an adjustable one. I spend about 50% of my time standing and 50% sitting - standing the whole day is also associated with health problems.

Matting is essential, even if it's just some unfashionably padded shoes. Even working summer retail jobs as a teen it was evident that standing for long periods of time just hurts if you're not standing on something. You may notice that cashiers often stand on pads.

I don't think it takes much, though. I stand on what looks like a Shamwow yoga mat.

Yes -- I got a custom mat. I feel it is crucial to be able to withstand long hours standing. http://www.amazon.com/gp/product/B003BYRDK2

I just use regular flooring (carpet). However, after reading this comment I'm thinking I should get some sort of matting! Haha To be honest, I just hadn't thought of doing that.

I just stand on the regular flooring (which is carpet in my case). My shoes have a relatively soft insole though.

stand barefoot on office (read: hard) carpet. I do however find that I need to sit down for a few minutes every hour or so.