Knee pain is the biggest cause for me not to ride my bike to work or recreationally for that matter. As I was reading Recumbent & Tandem Rider Magazine, I saw an ad for Kneesavers. I visited their site to see what they are all about:
Kneesavers are custom pedal extenders which are designed to be placed on your bicycle between your bike pedals and the crankarm. By adding our precision spacer, up to 20 degrees of toe-out can be gained (your feet are essentially wider apart). This modification can often minimize or eliminate hip, knee, ankle or foot pain for many people
I will be installing the Kneesavers soon and give them a try on some hilly terrain. Stay tuned for my first impression.