Pay & Sit is a
user-pays park bench.
The bench contains metal spikes embedded in the sitting surface, which are retracted when the user inserts 0.50€ into a coin box; the bench beeps when the sitting time is about to expire.
Pay & Sit is not an actual product, however, but the work of an artist named Fabian Brunsing, commenting on the logical extremes of user-pays culture and/or the privatisation of public space. There is no guarantee, however, that some local authority (or some firm contracted to manage (privatised, ad-funded) public parks by one) won't try something like that at some point.