I realize this is a really old thread I'm replying to but the key pictured in the thread is the closest I can find to the keys I have no idea what they're for...
Here is a pic...

Do you have any idea what this type of key is and what it would be used for?
I've searched the term dimple key and notched key with grooves (it has a notch at the tip), 3 dimples on one side and 2 on the other... I can't find anything with those terms but this thread popped up so I thought I'd follow up...
Originally I thought it was for luggage but it doesn't look like any luggage locks I can find.