Class Options for Helping Random Players

I know the 3 work for sure but the bard songs is where I believe you have to be party

Thank you fletches and Skies! =D I really appreciate the responses.

Bard was a job I was thinking about going for with conjurer heals on the side, but if the songs only buff party members, I may reconsider that. Still great to know that there are buffs which will work on random people!