This instructable used...
1x Kingston Data Traveller 1GB - Chosen for it's reliability size and low prices - I got mine for 1.60.
1x Donor keyboard key - I used the shift key because its easily obtainable, easily recognisable and big enough to house the usb key.
1x Tube of general all purpose filler - You could also use epoxy or hot glue if you like.
1x Pot of acrylic paint to match the cooler of the keyboard key.
A wee touch of tippex (or "liquid paper")
And the tools...
I used a decorators sanding block but sanding paper would do.
You might need a small drill bit to create a small hole on the key so an LED can shine through IF the key you use is completely opaque.
You might want a paint brush - obviously to paint with.
This Instructable has no real reason to fail, it worked for me and uses techniques which should cause no damage to your own items. Nevertheless for legal reasons i must disclaim= follow this instructable at your own discretion and in knowledge of the risks, i accept no responsibility for damage to USB drives as a result of falsely following this instructable, or this instructable not working for you.
Step 1: Bust Out the Electronics!!
Take the side which isn't the LED side off first, once you have the drive itself out then move on to the next step.
Step 2: OPTIONAL PRECAUTION: Sealant
Step 3: Adapt Your Key
Once you've done that take a craft knife and remove a section on one end of the key that is the same size as your usb connector.
Step 4: Pack Out, and Cover Up
I then precision engineered a slice of a tic-tac box to cover over the whole thing. This sat just on top of the drive about 2mm lower than the top of the key and filled the whole space of the key. This step is to fill up some of the space already so that we need use less filler/epoxy/hot-glue when we start the process of finishing the drive.
Step 5: Fill and File.
I built mine up gradually, laying in one lot of filler, letting it dry a little, compacting it, and refilling the key. Repetition of this technique allowed me to build a dense protective layer of filler in the key. Because it was compacted/pushed down it became stronger.