Drawing "just for fun" has many advantages outside of the immediate satisfaction one gets from messing about with crayons.
Online communities are a fantastic way of building friendships and getting exposed to new things (techniques, a new online music site - whatever).
Third Rail Design Lab (R3) is one of the good ones with artists at all levels discussing comics, film, music and art (among other things) in addition to hosting a weekly jam open to everybody.
This was recently done for one of the jams . . . I'll continue to post these weekly sketches here.
Thumbnail is Col-Erase blue pencil drawn in a sketchbook
(during "Big Bang Theory").
FInish is the scanned thumbnail inked and shaded in Photoshop on a Cintiq.