I watch Dexter with my parents. We all enjoy the show.
I stock up each season's episodes on the DVR until I have the whole season or almost the whole thing, so they can sit and watch the show straight through, without waiting for the weekly fix. Best way to watch anything storyarc-ish with my mother, really. ;)
This usually ends up with wactching the show in mid to late December. Which means we have developed an almost unspoken tradition of watching Dexter every Christmas.
Which is kinda messed up, really. ;)
Got any odd traditions for Christmas?
My fave Christmas movie is Die Hard.