I can't say I ever thought I'd be this impressed by what is basically a glorified recipe website, but I am.
Here's the gist: They have a big database of recipes which you browse and add to your list of planned meals. From this, a shopping list is created for you, which is organized by aisle, and accessible on your iphone so you can use it in the store and cross things off. I believe it costs $1.99 per week, although I am currently using a free month by being referred by a friend via facebook.
Other sweet features: You can set up "my diet" where you can have it suggest low fat/low cal/low carb meals exclusively or just more frequently. You can have it exclude recipes with certain ingredients, such as shrimp since my wife is allergic. You can narrow recipes by <6 ingredients or
Before finding this, I was basically useless for grocery shopping. I can improvise a meal from the pantry in 30mins or less usually (bread crumbs+tuna+egg = tuna burger!), but at the grocery store I tend to gravitate toward frozen meals, kit-in-a-box meals, etc, and hardly ever buy fresh produce, meat, i.e. actual INGREDIENTS. Last night we had Moroccan chicken and couscous. It was really easy: cut up some zucchini, tomatoes, garlic, salt, lime juice, dried ginger, pepper, cilantro, and some chicken breast. Cook it in a big skillet. Cook the couscous on another burner, and done. It was delicious, made from fresh ingredients, and healthy. Tonight is mahi mahi filets with a salsa made from red onion, avocado, and orange with rice. Our grocery bill for the week was less than we are used to seeing, too.