My worst present was the ugliest, hand-painted china owl one could ever clap eyes on. For some very strange reason my Aunt gave me a Russian doll for my birthday last year....I was 43!!!
I would happily have swapped them for your unwanted wincyette nighties. They may not be very attractive, but at least they are warm and cosy on a cold winter's night.
Actually I've just remembered the hand knitted gloves that my Nan made for me. She gave me three (?) and they were all different sizes! That's definitely got to be the worst present I have ever had.