For me the saddest Animes were Clannad and Elfen lied they were the best i seen so far even thou i am not really an anime fan. But i highly recommend it for anyone who hasnt seen it to watch it :'(
DUDEEE this is the first thread on the list, and it's exactly the same as yours >_> https://www.romulation.org/forum/index.php?topic=29490.0