So I just marathon'd Clannad with a couple of friends. 48 episodes including the OVA episodes (we left out the summary episode though), took 22 hours in total, with a combined break duration of 4 hours.

I haven't ever watched for this long at a time before and I doubt it'll happen again anytime soon. But it was awesome.

I'm currently in the process of watching Steins;Gate with my dad (10 episodes in, he's pretty bored, I have faith it will change by the halfway mark) and my brother's christmas present for me was that he will watch Clannad with me. I don't mind seeing it a third time, though any more than that feels dangerous. Don't wanna ruin the series for me.

All the while I still try to watch some NANA every now and then. A friend of mine is also watching it and is now quite a ways ahead of me and told me that the series gets pretty good. Motivated!