I usually ride this for long distance commuting. Yesterday I used it on a Slalom course I made..and with a cable cam! Incredibly hard to weave in and out on this!

https://www.youtube.com/watch?v=PuaPdEsLBdI

How hard is that to learn?

You make it look so easy! BTW, where do you get 36" tires?

Really depends on a lot of factors, but in general, if a person can ride a bike, they have all the balance needed to learn. Practice and determination also play a large role. Most that learn to ride successfully often can learn the "basics" within a few days, practicing maybe 30 minutes a day.

Free mounting is very important to learn, so you don't have to rely on something or someone to help you mount. Once you learn to free mount, the skills that you learn from there on are totally up to you, but the skies the limit! Also, the smaller the wheel, the easier to learn. Most learn on 20" or 24", then move to the larger wheel.

Where's a good place to buy a used one?

There's not too many used ones for sale since most people who have them, hang on to them! But maybe craigslist, ebay, or if you want to check out new ones, there's www.unicycle.com and www.cokercycles.com

Doesn't look easy in the least bit.

There's a 13 year old girl on my block who can do it.

I did a 100 mile bike ride through NYC, and one guy on a two-speed unicycle went faster than I did.

So, uh, unicyclists impress me.

I'm hoping I can handle it, I want to mix it up a little bit.

You'll love it!

The 36er is definitely harder to ride due to the heavier, more sluggish wheel mass, and also they usually have shorter cranks which is great for speed and less leg movement, but also much harder to control and takes longer to stop. But they are a trip to ride and on flat it feels like it almost goes by itself with a kind of "flywheel" effect. It's a feeling of perpetual forward motion. I'd like to do a century, and so far I've ridden 50 miles in one go.

www.unicycle.com or www.cokercycles.com. the first link has more types to choose from.