If you're after a thrifty option, your best bet is this Asos Tank. It's a wonderful item, while not very costly. In this price range, you can also check out this Urban Outfitters Tank. It's also a popular item and won't break the bank. Or you can opt for this Aqua Tank. This item has all the potential to become a powerful player in your wardrobe.
If you want to splurge on a luxury piece, then what you're looking for is this Theory Tank. It's more expensive but worth your money. Another product we're drooling over is this St. John Tank. It's costly but you get what you pay for. Also check out this Sportmax Tank. You won't regret the money spent!