After a lot of mining of adamantite I finally got my JC skill to 350. I spent most of my playtime today flying around Blade's Edge Mountains and mining adamantite!
...though I took time out to raid Ulduar--my first endgame raid!--and do a random.
Still: once I got my JC skill to 350, I was able to get "Grand Master" JC; and then I bought
FIFTY-NINE RECIPES
...for gems.
I'm not kidding: when you hit 350 in JC you get access to fifty-nine recipes. I had the gold, so I bought them all. And I ran the JC quest which you get from the JC trainer in what's-a-call-it in the Borean Tundra. (I can't recall the name of the town. The ship goes there from Stormwind.)
Running the random (we got Culling of Stratholme) paid for all those recipes, though, so that was nice.
There's another achievement I got for getting my other profession to "Grand Master" but I can't remember the name of it.
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Here's a small version of my current desktop image:

This is the scene where Yuki Nagato hands Kyon the bookmark with the same alien writing on it as what Haruhi wrote on the school grounds in her first year of junior high with the line marker. Kyon says, "Don't tell me, but this isn't actually an alien language, is it?"
This is Yuki not telling him.