You could drive another chain from the left-hand pedal to power a small suction fan -- you just need a couple of brackets to mount the fan and the tube. Simples!
For no reason other than it is my favorite poem and it seems appropriate.
When I was small and five
I found a pencil sharpener alive!
He lay in lonely grasses
Looking for work.
I bought a pencil for him.
He ate and ate until all that was
Left was a pile of wood dust.
It was the happiest pencil sharpener
I ever had.