I'd LOVE to see someone come out with functional attire/garments for pump wearers...especially women who like to dress up! I'm a 27 year old pump user in Miami, land of 'little clothing as possible,' LOL. It is hot here almost year round and people don't wear much clothing. This makes it very hard for me to "hide" my pump. I usually end up sticking it under my bra, but this can make your bra look bumpy and weird. As far as dresses go.....get some Spanx or similar boy shorts and stick the pump in there! The Spanx are tight and hold the pump in place pretty much anywhere "down there." I've never had it drop/fall out using this method (unlike the bra method).
I've found absolutely no way to hide my pump at the beach/pool (where I spend a lot of time). Almost all of the people in my condo have by now asked "ummm, what is that?!" after seeing my patch, line and pump down at our pool. I've patiently explained my pump to dozens of people at the pool now :) People at South Beach tend to be obnoxious and stare at it, but when I'm there I just try and ignore their rudeness and stupidity! It can be hard, of course.
Definitely keep me posted if you come up with any solutions!! This may sound like a shallow topic, but not everyone wants to have their pump the center of attention everytime they go out!!