Yea, I don't think sharing uses would be revealing... however, you might want to look at Garcia's "Satisfaction Gauranteed". It's an all double backers routine.
If I am not mistaken Richard Sanders show Volume 3 has some neat applications for double backers....also Jay sankey has numerous effects using double backers my favorite being Public Transit...I think its called that..lol..but Daniel Garcia as mentioned has a few effects also