I originally caught a random episode of Band of Brothers on TV; I thought it was amazing, so I rented the first two episodes and loved them. I went back to rent the next two, but they were out all week. Finally, I said screw it and bought the boxed set. I went home prepared to marathon the whole thing, and I wanted to do it right, so I watched the first two episodes again.
A friend of mine called and asked what I was up to, and when I told him, he said it was an awesome idea and he'd be right over.
So, I watched the first two episodes AGAIN and we watched the whole thing, finishing at around six in the morning Sunday.