[P]

Recently someone loaned me some discs which were in a style of case I'd
never seen before.

They were clear slim slightly rectangular soft plastic cases with rounded
corners. At one end there were two indented thumb tabs to open the case,
but instead of opening right out (with a hinge on the other end), the case
opens half way down, like two flaps on both sides of the case, enabling you
to take the disc out easily by the edges or putting your finger in the
centre hole. They were really great and I'd love to get some. I looked for
any information on the cases but all they said was "patent pending". Any
ideas?