Andy's grandpa always used to make flank steak supposedly, it's kind of tradition in his family. I've never had it, but I have his recipe and have made it a few times in the last year. Super easy. I'm sure there's a better, more complex recipe somewhere out there, but this is so quick and really good.
Poke holes every few inches in steak with a fork. Sprinkle thyme on a flank steak and cover with soy sauce (I marinade mine in a ziplock bag, you can do it in a cake pan too). Let marinade for 4 hours or whatever. Grill. Cut very thinly against the grain-this cut of meat is very very lean and can be tough, so this step is absolutely necessary.