In my university days, I used to perform at an senior living facility with a group of fellow student musicians. We used to play individually, like at a recital, but sometimes we accompanied each other or just jammed. The seniors in the audience and their family members used to love singing along to the songs they recognized but also enjoyed the songs they didn't know. Sometimes I tested out instrumental pieces I was in the midst of composing. It was overall a very fun and meaningful experience. I wish I could still do something like that. The funniest, however, was when a new student joined us and tried singing contemporary emo songs in an atonal way. At one point, he implored the rather confused audience members to sing along. The admin person of our volunteer group had a word with him in private after that and he never joined us again.