The Power of a Good Business Card

Today I went to the Bibliotheque Nationale et Universitaire.
It is a good place to photocopy articles from 1900 on.
But it is not my favorite place to spend long stretches of time. It is not air conditioned, nor is there any place to eat or drink, and the bathrooms are the second scariest place in Strasbourg. (I have a lot of negative nostalgia associated with those bathrooms.)
Unfortunately, one of the main manuscripts I came here to see is in their collection, and they are the ONLY archive that will not allow me to take photographs.
(They do offer a photography service, but it is quite expensive per page, and when you have 150 pages, it adds up quickly.)
Well, I got there bright and early when the doors opened, and headed up to spend the day with MS 752. The librarian retrieved it for me, and then a potential crisis loomed:
I had forgotten my ID card.
Now, I had my library reader's card (you have to have it to get in and out of the library, because the bar code on the card lets you past the automated turnstiles.) And, knowing that I would not get anything to eat except the Clif bar I brought with me (my last one!) I did not bother to bring my wallet.
At first, it seemed that without my ID as collateral, they would not let me have the manuscript (even though I couldn't have taken it out of the rare books room where the librarians constantly have all readers under surveillance.)
But they agreed to accept my business card in lieu of photo ID. (!!!)
I guess it helps that I am listed as 'assistant professor'; that seemed to make an impression!