This organizer can store 4 SD cards, 4 USB drives and 10 Micro SD cards.
This part is a remix of http://www.thingiverse.com/thing:674303.
I've extended the part to hold more USB and micro SD cards. Increased the depth of the micro SD card slots to allow the card to slide further in and be more secure. I've also added holes in each slot to allow debris to fall out the bottom and away from your storage devices.