Heck, why not just change to a smaller set of chainrings up front? Most cranks can be downsized some on ring size. Then you shorten the chain a couple of links to accomodate the shorter overall length, and you're set!
I changed my hybrid Sugino crank from 42-52 to 36-46. Made all the difference. I really appreciated the lower gearing, and didn't really miss the highest ones.