What made me happy? Singing a trio with my daughter (12) and son (15) - in three part harmony; all the lullabies I sang long ago are paying off. We get to sing the song in church next Sunday - "Siyahamba", a South African folk song, translates to "We are marching in the light of God". (There are many wonderful renditions of this song on youtube.)
Pure joy - no accompaniment is needed, we just bring our voices and SING!