Buy Crazy Arms here!
Check out the FLICKR group for Crazy Arms here:
I have always loved minifigs and customizing.
Although if you wanted a more dynamic arm position, you are a somewhat restricted or in need of jury rigging some flex tubing to get the job done.
I just finished a batch of these custom arms and have them now available for folks to use. The replacement 'Crazy Arms' are highly engineered in that they accept the existing hands perfectly ( they click right in ) and POP in the existing torsos with a nice click. They can easily be swapped and changed out.