What are some good Singing Trios?

My friends and I are planning on singing in our talent show this year. I was wondering if you knew any good trios that we could do. We all have pretty flexible voices, and could go down to probably to a D... sooo nothing too low. We did boogie bugle boy last year and it went really well. We'd like to do a 70's or 80's era song, but we have open minds and are willing for any suggestions! (Though nothing to spiritual) We want to have fun, and let the audience have fun watching us! Soooooooooooo what songs, and where to get sheet music would be AWSOME!!!!!!!!! Hope you could help Thank you