Meatless Monday has been part of American culinary culture since it was introduced during World War  I (along with "Wheatless Wednesday") in an effort to encourage voluntary rationing. Since 2003, it's been encouraged by the John Hopkins School of Public Health Center for a Livable Future, along with numerous other good health groups. You can become part of the movement at the various branches of
Tender Greens, where they serve a Meatless Monday menu of heirloom tomato gazpacho, warm baby Swiss chard, white corn chowder with crispy okra, ricotta gnocchi, foraged mushrooms and peppers stuffed with Himalayan rice - and, of course, most of their salads.
[Also see: The 10 Tackiest Restaurants in the U.S.]