The perfect gift for a Dr. Who fan! The 4th (and best) Doctor's TARDIS key.
This TARDIS key is a duplicate of the actual key. So, yes, I guess if you ever run into a certain Type 40 time capsule, you'd be able to take a peak inside.
If you woudl like a TARDIS key for your personal time capsule,
head on over to the Trade Collective's other listing which allows you to upload your own image to the back of the key.