It is possible, some people use the js click() on a hidden file form but it only works on IE so I did some research.
Then I found the yamago upload component. Using its principles I created a skinned browse button which sent the path back to flash, it works on pc/mac, pretty much every browser but opera. It was for a study I was doing into the browse button and possible skinning of it. I compared different skinning options by platform and browser.
Compatible: PC Windows with Mozilla 1.2+, IE5+, NN7+, Phoenix beta 5 Mac with Mozilla 1.2+, IE5+, NN6+, Chimera 1+, Camino
The page is here: http://www.syntonik.com/justin/brows...buttonmain.htm