What other hobby...

All of the above. 1500 bottle wine cellar, frequent tastings, bottle variation even with the world's finest crus of same producer and vintage, many more vagaries in viticulture than audio engineering. And let's please not even mention any aspect of human relations, which are not, ahem, "hobbies." But tweaking an audio system can take forever, as the Nth degree recedes endlessly, "boats against the current." Unless you're millercarbon, who has got everything right, a fact I acknowledge with the greatest respect and admiration. What's left after that but to read The Brothers Karamazov in Russian, Tale of Genji in Japanese, Proust in French?

Musician... hobby or pro. Cycling...

36 Years of flying radio controlled helicopters

@dekay.....Why do I get the impression that you're Not refering to small mammals? ;)
I'm allowed to 'watch' all I want, too....
I'm NOT allowed to get grabby, drool, or whip my head about in public to verify what I just saw...;)

My cardioMD told me to stay away from sildenafil.....
"Lasts too long...I don't want you to waste all of our expensive handiwork."
So...timing and...'co-ordination' becomes a major factor. Into the Blue...;)

We work in wood, so have 'toys' basic to esoteric (a Prazi-equiped Bosch worm-drive saw, anyone?).  Metal and plastics are part of my skill set.

Jack of all trades, master of some.  Find quantum physics adorable; makes sense of the senseless, and something to place blame on.

Spouse gave me a t-shirt lately:

Free Contradictions! $1

It's a Life. *G*

Next....

Not a downer if you get it... but, preparing to die. (Hopefully not for a long time!) The older I get, the more my perspective on all the activities and fuss evolves. "You may die a hundred deaths without a break in the mental turmoil. Or, you may keep your body and die only in the mind. The death of the mind is the birth of wisdom."