i've had some success with a few early spring gardens. swiss chard "neon lights" is really cool.
purple top white globe turnips, detroit dark red beets, heirloom beets, danvers half long carrots, mesculun mixes, cos cob romaine, broccoli rabe, snow peas, and asparagus have all done well in my garden in the earliest season.
if you do nothing else, plant asaparagus crowns for next years harvest, if you have to room. fresh asparagus, picked, steamed and cooked within a few minutes cannot be compared to anything else. it's the taste of green; the taste of springtime.