2nd image is original art by Ikegami Akane,
here.
3rd is also an original, artist is soba,
here.
5th image is fan art of Mio from K-on! (found also in
imouto.
"1.04 group of people dancing" looks like Mitsudomoe, can't be sure, though, because I haven't seen it.
"2.58 guys drinking out of boots" is from opening/ending (?) of Hetalia Axis Powers.