Here's my cutie patootie 5-year-old niece, Lorin, sporting her new ribbon tank:
It was made from a free pattern that can be found here:http://www.kerriesplace.co.uk/exotictank.html
Sorry I've no photo of the back, but you can see it in the pattern link - it's a crossback, but the straps can also be fastened uncrossed to allow a growing kid to get one more summer out of it.
Two more things: the pattern is modifiable for adults, and the yarn called for, Phildar Exotic, is discontinued. More deets at der blog, below.
Now if summer could just hurry up and come back so's I can make me a grown-up version!