So you probably don't expect to find any spies or undercover activity going on in Milwaukee, Wisconsin (and you probably wouldn't), but what you can find there is a restaurant devoted to espionage called Safe House. And I mean that you literally have to find it. The entrance is hidden somewhere in an alley way, and even after you figure out which door it is, you need to offer up a worthy password to get in.
Once you're inside, the spy theme continues. I'd tell you more about it, but then I'd have to kill you. Just kidding! Covert activities include finding the secret phone booths and accepting missions that take you on a tour of the restaurant, which is filled with spy memorabilia. The menu features items such as the "squeak-easy" (batter-dipped Wisconsin cheese curds topped with a secret sauce, natch), and the drink of the house is, of course, the martini. Mmm ... cheese curds and martinis. Offer me that combo and I'll tell you anything you want to know. Guess M16 won't be hiring me anytime soon.