has anyone said bent-over flys yet?
and even light weights held straight out in front of you, elbows about 90 degrees, and push-together / pull apart kind of motion seemed to work something in my back quite hard. I hope there's a technical name for that cos my description sucks
I also do some fairly random waving-around of light weights, since I figure this has got to help abs, back and especially core muscle strength in the body too... won't gain you much muscle mass but worth the effort I should think.