gd has donated clothes to a charity auction, money to a children's hospital(has also had money donated in his name by fans). he visited and spent time with that little boy who was/is sick who has the same name as him. gave him toys too.

seungri donated 100 sacks of rice to his hometown, gwangju(and is said to do so every year from now on). notably, he runs an academy to train idols. people might see that more as a business investment but i honestly think he means it when he says he does it for the good of it.

daesung does a lot of chruch volunteering. he basically lived at the church and helped volunteer during his "scandal" in 2011. I feel that his trying to make amends with the family of the deceased was admirable.

also there was a little girl who was very sick and she was a huge daesung fan. when daesung heard he visited her in the hospital numerous times. the rest of big bang also made time to visit her. they gave her signed cds and took pictures and even promised her a vip ticket for big show 2011. sadly, she died before the concert.

this is all off the top of my head, any bb anons wanna chip in?