If you're a frugal shopper, your best bet is this Eberjey Tank. It's a popular piece, while not very expensive. Another nice option is this Tart Tank. While the price is not too high, be sure that this product will become an excellent addition to your wardrobe. You might also want to consider this Cotton Citizen Tank. The price is very reasonable, but the effect on your wardrobe will be pretty fantastic.
If you're looking for something in between pricewise, look no further than this Joie Tank. This item won't break the bank, but absolutely indispensable in your wardrobe. Also take a look at this Shoshanna Tank. It's an attractive option both price and quality-wise. Check out this Wilt Tank too! Great value for your money.
If you have enough to afford it, why not look at this Joie Tank - a great luxury choice. While you're at it, also have a look at this Akris Punto Tank. Yes, this item is expensive, but it does not mean it's not worth it.