This is really an interesting thread.

I am using Poser 5 and Vue 4 for illustrations
for the book I am wrinting (for those of you
who speak German or just want to look at the
pictures: www.d-u-l.de).
Actually, this is a hobby for me which I was able
to make money out of, but it is hardly worth
mentioning it, not more than maybe 10 Euro per
month.
But I really like 3D programms, especially
Vue. I have never seen a software that produces
so good results so easily.
I wish I had more time for this ...