If you are in the UK, contact CRISIS - they used to be called Crisis at Christmas and specialise in helping out those less fortunate - you spend some time in the shelters, doling out food, going round making sure the street sleepers have at least one hot meal/drink/blanket, and occasionally giving out gifts that people have donated to foster homes, that sort of thing.Many hospitals also run Christmas visiting volunteer lists, but that can be really harrowing as only the worst cases are kept in over the holidays, and accidents are more frequent.
We used to try and have one day without the TV on, usually Boxing Day, but the advent of the bratling put paid to this. Still, try and get out to your local park, if only for a post prandial perambulatory perusal of the wildlife.
LTS