Actually found a good eye/hand exercise when I started using tablet, will see if I can find it...
Never worry about the time limit - you can draw ANY subject whenever you want. 24 hour limit is mostly to assure that we get at least that time to draw before a new subject pops up. Good for my discipline to have a theoretical limit. But - I can't repeat this too much - main purpose of this thread is to get us DRAWING, and posting our efforts. 
Great subject, loads of fun. 
OK, here is a tutorial including that exercise (don't know whether you have to register to see it though):
http://forums.cgsociety.org/showthread.php?p=3629771#post3629771
Well, let's make the next subject official then:
Sketchstorm #9: Your favorite musician (playing an instrument)
"Every child is an artist. The problem is how to remain an artist once he grows up." - Picasso
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