Mmmmm... I don't remember exactly how many times I've watched each but here's the list:
You're Beautiful: I've watched at least 3 times complete and I've several other episodes more times.
Coffee Prince: As Lis said, it's Coffee Prince, what else can I say? I think I've watched it 4 times
Proposal Daisakusen: what can I say? It's YamaPi, and I really relate to the story. I've watched it 3 times
Hana Yori Dango and Boys Before Flowers: I've watched both versions 2 times. I've watched the Japanese version twice because it was my first drama and I loved it and the Korean I didn't like it so much but halfway through watching it, my brother started watching it with me so I had to watch it twice.
Hana Kimi: I've watched it twice and could still watch it a lot more
I litre of tears: I've watched it 3 times and ended up crying a lot always.
And....I thinks that's it