If you're a budget-conscious shopper, your best bet is this Prana Tank. It's a great item, while not very costly. Why not also check out this adidas Tank. It's a product you're bound to love which also doesn't cost too much. You might also want to consider this Nasty Gal Tank. The price is very reasonable, but the effect on your wardrobe will be pretty fantastic.
If you're looking at it like an investment piece, then you absolutely must check out this Alexander Wang Tank. This product seems pricey, but it's worth it. Another product we're drooling over is this R 13 Tank. It's expensive but you get what you pay for. And one more item you might be interested in is this 3.1 Phillip Lim Tank. 'Cause you deserve nothing but all the finer things!