Several posts here and there lately have made mention of restaurants that focus on using local ingredients. While I don't think anywhere comes close to the goal of "locavores" to only use products grown or harvested w/i a 100 mile radius - check out www.locavores.com - I think any restaurant that's making an effort to use local product and support local farms, fishermen, etc. deserves notice.
Here's some I can think of that I've noticed recently in Miami ->
Michael's Genuine Food & Drink - lots of local fish - black grouper, pumpkin swordfish, pompano, snapper. Pretty sure the tomatoes for the panzanella salad and other items are usually local (and ripening on the kitchen counter). Would be willing to bet the frog legs for the "buffalo" frog legs are local as well. As MD has recently detailed, has also recently been using burrata and farm fresh eggs procured from the UES Greenmarket.
Michy's - a "fish of the day" when I was just there recently was a local pumpkin swordfish, another nice dish not currently on the menu was an orrechiette with "loxahatchee greens."
Table 8 - local tangerines in a green bean and prosciutto salad, local oak-leaf lettuce, Florida clams, grouper, snapper.
Talula - usually use Key West pink shrimp for the shrimp tamale appetizer and other dishes.
Yakko San - on my last visit they had a local octopus ceviche, also a local shrimp kara age (lightly coated in corn starch and fried whole - shell-on, head-on - eat the whole crunchy thing).