Very flexible list application from SplashData which can be used for groceries and anything else you want.

SplashData has been around on the Palm platform for years - often with associated desktop clients, but with the advent of the iPhone, they've (naturally) tried to make inroads into that market, as well.

With SplashShopper, they've succeeded pretty well. The best feature of SplashShopper is its IP-based syncing with the iPhone version (which, annoyingly, you have to purchase separately from Apple's AppStore). If you own an iPhone and a wireless network, you can simply do all your work on the desktop client, and then have it sync immediately to your iPhone for your shopping trip. No more emailing shopping lists to yourself, no more iPhone lists which lack the ability to check boxes, cross items off, or delete things.

Only slightly behind the sync ability is the ability to create multiple, unlimited lists for whatever you wish. SplashShopper comes pre-loaded with about a dozen (groceries, gifts, music, movies are just a few), but you can easily delete the ones you don't think you'll use, and add as many more as you wish.

Last but not least, for those who do a lot of grocery shopping, there is the ability to import items into the grocery list specifically from the older HandyShopper, the new MacGourmet Deluxe, or a CSV file.