I had a smart diesel and a Prius at the same time.  I still have the Prius,
got rid of the smart pretty quickly.  I don't see any point to the smart
unless you need a really small car because of parking issues.  The Prius and
the smart cost about the same to drive, per kilometer, where I live.  But
the prius is a much nicer car to drive, and much larger.  The smart diesel
is slow, loud and harsh feeling.  Having only two seats and very little
cargo space means the smart is a second car for almost everybody.  A used
smart diesel in Canada is about $5000 - $9,000, so it's a few thousand less
than a Prius.

Gary
www.vwrack.com