Might sound kind of hokey but I enjoy volunteering. I've worked in soup kitchens during the holidays, as well as collecting donated food items (non e-coli) for baskets for the less fortunate. Done the walks and bike rides for cancer. Every year I've been involved in repainting local elementary schools (which my kids love to do too) as well as the dredded PTA volunteer raising money for playground equipment, books for the library, computers for the classroom. One of my favorites has to be the yearly weekend round-up cleaning up the desert, (maybe it's the free tee-shirt). It's amazing how many people think it's their private dumping grounds. And yes I work full time just like you so find a kid and read a book to them it will make you feel good.
Peace