One of my friends showed me a youtube of The Battle of Evermore that Page & Plant did with some Indian musicians. TBH, although I adore Indian music, I think this is a terrible arrangement and version of the song.
Starting at 00:06 of the video linked below, there’s a guy playing a keyboard instrument with a hand crank. My friend was like, “Look at that! What is that?” I said, it’s a harmonium. But the wiki page on harmoniums (harmonia?) makes no mention anywhere of a crank.
Unless I’m completely high, I would say that’s a hurdy gurdy, man.
Looks like a Hurdy-Gurdy.
I just spent 45 minutes trying to figure this out only to be double ninja’d.
It’s a Hurdy-Gurdy.
(OK maybe 20 minutes)
Oh yeah! Hurdy gurdy! I knew it started with “H.” lol. Thanks everyone!
You made my day and I’m not even dressed yet.
Hurdy Gurdy, as has been mention. IIRC, they were still using it (live) at the Page Crowes show.
Here’s a really good explanation of how they work (a lot of this guy’s videos are really good).
In short, it’s probably most comparable to a violin.
[Moderating]
Moving from GQ to CS.
Want to make your own? A cool company (US Gears) makes a laser-cut model you can assemble.
Sounds pretty tinny, but it works… and looks cool!
ps: Thanks, Donovan. I can’t type the word Hurdy Gurdy without hearing it with way too much vibrato…
Soupy Sales joke: What do you call a strong canary cranking a music box?
A sturdy birdie with a hurdy-gurdy. 
To be fair, you’re not exactly going to confuse a regular sized hurdry gurdy with a hammond organ. They’re pretty tinny to begin with.