Why would Tesla Motors CEO Elon Musk take a Sharpie to the sun visor of an all-but-new Tesla Model S electric sport sedan?

It wasn't a question we'd considered until a reader tipped us off to a photo on Flickr that showed just that.

And we were intrigued enough to contact Tesla Motors [NSDQ:TSLA} to ask just what was going on here.

The photo is one of a set of 15, dated last Saturday, collectively labeled "Elon Musk visits Austin," taken by local resident John Griswell.

"Owners showed up early during the opening weekend of our store at The Domain in Austin, Texas," responded Tesla communications manager Shanna Hendriks.

"Elon was there at South by Southwest to give his keynote address," she continued, "and he stopped by the store to say hi."

"Owners asked him to autograph their cars--and he obliged!"

For background, you should know that the first, priciest, and potentially most valuable Model S cars are the first thousand or so off the production line.

They have pretty much every feature you can order on a Model S, plus special paint and trim, and they're designated the "Signature" series.

Each one carries a signed nameplate with its limited-edition serial number.

Always wanted a "signature" Model S, but missed out on the pricey first edition?

There you have it.

If you're a Tesla Model S owner, and you want to make your car into a rare "Elon Musk Signature" edition, find out where the next Tesla Store is opening.

Then drive there--with luck it'll be near the company's growing Tesla-only Supercharger network of fast-charging stations--and ask him politely to sign your car.


[hat tip: Brian Henderson / photo: John Griswell on Flickr]


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