AAAAAAAHH!!!!! I'm so SLOW-brained! I only JUST NOW realized that the "compact double" crankset on my Surly Cross Check will accept a 3rd (granny) chainring! Holy toledo! And with the bar end shifter, all I'd need to do is adjust the limiter screw and finagle the spacing and I'd have a TRIPLE. (already has a long-cage rear der to handle the chain)

WOW!!!!!!

duuuuuude, what an awesome utility bike!