We have done "Mairie's" Wedding at one and "Come Write me Down" (aka The Wedding Song) at two others although you do have to watch the audience joining in the repeats and slooowwwwiiiiinnnnnngggggggg down the chorus in the Wedding Song.
Oh yeah a group of us also did the Bryan Adams Song from Robin Hood "Look into my Eyes or whatever it's called) at another.
ALL couples are still together too.
JohnB.