Dirk Ploos van Amstel has created a seesaw for children that converts to a bench.
SEESAWseat/seesawSEAT is a seewsaw and bench in one. Says Ploos van Amstel, "It is very easy to adapt to the specific situation and needs... play equipment during day... elegance (to drink a glass of wine) in the evening."
The bench folds in the middle, by folding over one side the feet are joined in the "new" middle to create the pivot. Handles for both extremities are folded into the bench surface and can be pulled out to seesaw.