FOODS IN SEASON NOW
artichoke, arugula, asparagus, corn, cucumber, fava beans, kohlrabi, peas, radishes, rhubarb, spinach, zucchini
FRUIT & NUTS
apricots, cherries, grapefruit, lemons, limes, passion fruit, pineapple, plums, strawberries
FISH & SEAFOOD
List from Eat The Seasons, North America , a quick way to check in on what's in season, with tips on storing and preparing(not to mention recipes!). It updates regularly. Another great resource is How to Pick a Peach: The Search for Flavor from Farm to Table by Russ Parsons. Check out the side links, too!
Why eat seasonal?
1) This is what our ancestors did. Up until very recently in the course of history, foods weren't available year-round, and so when a particular item was abundant, it was enjoyed and savored, rather then taken for granted.
2) It encourages you to include both a greater volume and more diversity in the produce you consume, not to mention tasting better! When farmers choose crops to not spoil when they're shipped long distances, flavor looses out.
3) It's healthier; eating seasonally makes it easier to eat locally grown food, which means that chances are your food will be fresher, therefore more nutritious, and less likely to be covered in the more creepy chemicals used to keep food good until it gets to the store.