When we go out as a group we all try and find it seperately. Whe anyone spots it, they just move on as if they are still looking, and then you could kind of mention that they have found it. It gets comical when you are still looking and you look up to see the others looking at the trees instead of for the cache, and you know you are the big dummy that hasn't found it yet!! (Usually me)
If it is a really difficult cache to find, such as covered in snow, and we are about ready to quit, we just say, if one finds it, we have all found it! Then we have one of us sign the log for all with our "took this and left that".