The Pennsylvania Dutch Tour
http://bikepae.nationalmssociety.org/site/TR?px=1771092&pg=personal&fr_id=7551
The City to Shore Tour
http://bikepae.nationalmssociety.org/site/TR?px=1771092&pg=personal&fr_id=8150
Both rides are raising money for the local (tri-state) chapter of the National MS Society. They provide assistance to local people living with MS, as well as offer research grants to find effective treatments and perhaps a cure.
I'm looking for donations, people that want to join either team, (I'm going to start setting up some training rides) - but I think you can join a team and just volunteer without having to actually bike the routes.