I've seen pictures of bowls made from vinyl records, and decided to try it myself. I have a colander and a stainless bowl that fit together pretty tightly, which is what I used to mold the records. I put one record at a time in the oven for a few minutes at 200*F. After the vinyl had softened, I put the record into the colander and forced the bowl down on top.
The record cools in a few seconds.Neat! I think the next thing I would try is vacuum-forming. It would probably leave a much more attractive finish with fewer if any folds and overlapping sections.