Hi Bob,
I saw your post and did some research on the key because it's so unusual it bugged me not to know what it is.
The key is made by a company which also makes high-end safes. They're based in France but are also active in Belgium.
Here's their website. WARNING, it's an extremely annoying flash/pop-up site:
http://www.fichet-bauche.com/
(edited the link 4/17/06)
Here's a description of the company:
"ACTIVITIES
Fichet-Bauche is world renowned for its industrial and technical competence issued from its experience in high security markets. Its solutions guarantee the security of people, property, data and value flows.
Solutions for a safer world
- Physical secutiry, Automation
A specialist in safe deposit boxes, fireproof cabinets, storage vaults and automatons, Fichet-Bauche, with its expertise in electronics, offers intelligent and open ended physical solutions, with multiple functionalities. While accompanying its clients through their evolutions, the group constantly develops new concepts, such as the "mur d'argent" (money wall), a great success among bank automatons.
- Electronic security system
Fichet-Bauche is placed on the high security market with electronic systems for detection, access management and local and remote control operation. The group offers modular, evolutive and multiple application solutions.
- Remote supervision and Remote services
From its remote supervision centres, Fichet-Bauche ensures the security of its clients 24 hours per day and with its remote services, it can manage, act, maintenance and develop the systems installed, at a distance."
Here's a link to a security.org page which describes the lock and locking mechanism:
http://www.security.org/Search/VerityDetail.cfm?ID=635
"The system is a very specialized decoder that is for use on the French made Fichet 787 Pump lock. This rather complicated mechanism contains ten small levers that are activated by the unusually shaped cuts on the key. The lock is only found in high-security applications......"
This site has a picture of your key. Scroll down a little:
http://protections-vol.com/repro-eng.html
I think your key is probably very expensive/valuable to whoever lost it. You might look up the contact info for the company and contact them about the key. The company can probably contact the owner through a serial number or model number.
Interesting find....