What is the Coolest Diecast Bonus ever made?

If you bought a set of 5 LFA made by Tomica Limited, you get an actual replica of Lexus LFA's keys. Seriously. It's awesome!

I remember when i bought one of those, and attach the keys to my old Mercedes S600. Too bad when i sold the Merc, the key goes with her, i forgot to take it off. But seriously, it looks like the real deal. Only the real deal made out of Carbon Fibre if i remember correctly.

So, have any other cool diecast bonus you ever seen? Fire away in the comments!