First Lost, which I’m still mid-season 4 on my season 3 to 5 rewatch, then The OC in which all I wanted to see was the first nice and festive – The Best Chrismukkah Ever – gripped me so much so that I just continued watching without really knowing. I’m on the penultimate episode of the first season already.
I seem to have discovered the wonders of seeing what you have already seen. Going through the toils of Summer and Seth’s relationship in The OC once more is hilarious, awesome and the geek references never get old. It’s just a bonus knowing that in a few years they will be a married couple.
I’ve always re-watched Glee, because like musical films, the episodes lend itself to rewatching more. You don’t listen to a song once then never again, so it works nicely. There’s the extra addition of having the ability to just watch the songs and absorb in all the visual context-y goodness.
I just have to reiterate that with Lost, even though it’s a rewatch, its pretty much watching the show anew.