View ENTIRE contents on device and card

I would like to be able to view the entire contents of the internal memory and the card(if it has one).

Why?  I sometimes forget my thumb drive and would like to put a document or spreadsheet or that new d/l program etc… on the device to take with me.  I want to be able to see if its on the device/card or not instead of shuffling through cards trying to find which one I put it on.