LEGO USB Flash Drive

Take part your USB flash drive. I went with PNY's Micro Swivel Attaché flash drive because it's small and easy to take apart.
Build a stack of 2x2 LEGO bricks that's at least as long your USB drive.
Wrap tape around it to keep it from being scratched.

Attach the router bit and cut away the round post in the center till it is flush with the inner surface.

Vacuum or blow out the plastic shavings.
Place the USB drive in the hole and estimate where you will have cut to fit the drive.

Use the router bit to rout a slot that's the width of your flash drive.
Remove the shavings and place your flash drive in the slot to check for fit. It should sit straight in all directions but don't worry if it has room to move around since we'll fix it when we glue it in place.

Take the stack out the vise and remove the tape and detach the slotted brick.
Re-tape the remaining bricks in the stack and place it in the vise.
Repeat steps 3-5 to make more slotted bricks. Repeat until you have only one brick left to cut.

The last brick is for the cap.
Cut a cross so that the cap can fit over the head of your USB drive in all four directions.

To cover the cross notch on the cap brick, use a 1/3-thick 2x2 brick. It is 1/3 the thickness of the normal LEGO bricks.
Wrap tape around it and place it in the vise.
Cut the center post flush to the inside surface.
You can now snap all the bricks together to check for fit before gluing them.
Make sure the cap brick fits over the USB head.

Use super glue to glue the 1/3-thick brick to the top of your cap brick.
When the glue dries in the cap, place the next brick and the flash drive onto the cap.
Push down the drive all the way to the cap. This gives the USB head the most room to go into a USB port.
Take the cap off and make sure the USB contacts can still reach the USB port. If the contacts are too far in the stack, it means your cap is not long enough and more material needs to be removed from it.
Place the cap back on. Hot glue the flash drive in place with a tiny dab on both sides. Do not pour too much that it prevents the next brick from snapping on.

Dab a bit of super glue to the next brick and place it on.
Repeat the hot gluing and super glue the 1/3-thick brick to the bottom for your last piece.
Once the glue dries, plug it in your computer and test out the drive!