Maoz Falafel on Union Square East is apparently an offshoot of a European chain of the same name. The basic idea idea is that they give you the pita and falafel for a sandwich (assuming that's what you ordered, as I did), fill it up with one of three basic ingredients (hummus, feta, or eggplant), add in falafel, and then YOU add in the condiments. The condiments come in a little salad bar, and included pickle, sauteed carrots, a broccoli and cauliflower mixture, classic falafel-style purple cabbage, and a set of several "salsas" and yogurt and tahini sauces.
It's a fun way to put together a dish, although I made the rookie mistake of putting way too much into my sandwich and getting full about 2/3 of my way through the sandwich. Unfortunate, because this is a tasty sandwich. The falafel has a nice blend of spices and is not too dry. The place itself has a very small seating area and is a little drafty due to the door opening a lot. Other than that, though, it's great. I think it might be my second-favorite falafel after Taim at this point.