Interesting side-topic: how many hackers out there are also musicians, and what do you play? I started playing violin when I was 2, but haven't played so much since leaving college. Maybe we could get a quartet together or something... you know, "I'm starting a hacker quartet, BUT I'm still going to work on my startup" :)
Violin was my first instrument, but I've mostly played guitar for the past ten years or so. I guess I was a musician long before I was a hacker, and I see a lot of similarities between the two - the variety of things you can do, the amount of time it takes to become decent at either, etc.
Surprisingly enough I've never tried to bring the two together. Signal modelling/processing software...talk about 'hard problems'!
I took a similar path - violin for 9 years, then switched to guitar when I was about 16 (to be cool, of course). I didn't completely drop the violin, but guitar was my main instrument for the later part of high school. But then I picked the violin up again for All States my senior year, and kept doing it for college. Surprisingly it's violin that stuck - I still play a couple times a week, while I haven't touched my guitar in close to a year.
I've also dabbled in a bunch of other instruments - 3 years of clarinet in middle school, enough viola to play and (barely) read music, picked up a fife and tin whistle in Williamsburg, reasonably fluent on bass guitar, and I've been trying to teach myself piano over the past couple years, with only slight success.
The hardest part of learning to play (and to master) the violin is definitely learning how to use the bow. Actually learning how to play in tune is hard as well. It's just hard.
I play several instruments, but it's the violin playing that goes rusty quickest. Past a certain stage, you can get out of practice with just one or two weeks of neglect.
the article deals only with the mechanics but surprisingly, omits the really hard part - getting emotion to be depicted in the violin tone.
that's why I gave up the violin after 3 years.