Hi transient,

These are amazing:

Shimera Seamless Bra | Nordstrom

That is just one example of a "bralette"...the cups can stretch a lot and the straps are adjustable on this particular example. They are not nearly as binding as a sports bra. These are the nicest ones I have found (and I have tried a lot of them!). I have bought some at Target in the past but they were not as nice or nearly as comfortable, and also they offered less support. I am pretty psyched about this bralette...the ones I ordered just came today.

Oh I should add, you do have to order by your band size, and what I ordered is true to my size.

See step 1 for the band size below:

http://www.herroom.com/bra-fitting-a...FeMSOgodbVMAiQ