I used to have a toshiba laptop with a built in card reader (but i believe this is how most builtin card readers function) which would not show up until you inserted a card in the slot. With a single slot, especially on a laptop this isn't entirely useful, but I've searched all over for this functionality on a desktop media reader. I have bought 3-4 of them already (not just for this reason, for more reader types, speed, etc) and none of them do it. They all assign a drive letter continually.
My current multi-reader has 4-5 drive letters assigned to it ALL the time. When you add this to the 8 or so hdds, dvd drive, virtual drives, network drives, etc... its a fustercluck to say the least *chuckle*. I only use my media reader once every couple months, and when i do, its usually for a single port. There is no reason I should give up 4-5 drive letters, and clutter my "my computer" with these unnecessary items.
First, does any software exist that would remove the drive letters from selected usb drives (wouldn't want this for usb stick / removable hdd) and mount it (yes, i know, not really a windows term) whenever there was a disk inserted? If not, would anyone be interested in coding this?
One possible way (though i would prefer a better way if anyone knows one) would be to mount each of the drives to a directory thats out of the way. Then have some application scan each directory and mount it to a drive letter if its got something in it. This is not a preferred method, since this would require the card to have at least one file on it. So the card would not work directly out of the packaging when purchased.