(Not the greatest photo ever; blame the 6 year old photographer.)
I've made myself another top, from a piece of jersey type fabric my Mum gave me at the weekend.
It is basically two rectangles of fabric (quite a bit bigger than my body to allow for gathers) which I've sewn together into a tube.
Then I made a channel around the top edge and threaded through some fairly wide elastic.
I then added some straps, and hemmed all around the bottom.
It's very comfy and cool, disguising my mummy tummy!!
Actually this would work well as a pattern to make a maternity top, just using wider pieces of fabric and more gathers at the top.
(I would like to stress here I am NOT pregnant!)