Best yet... My MIL received a bright pink beanie hat (100% Polyester), that says 'Babe' across the front 
My own Secret Santa gift was fairly mild and nice - A mug with my initial on and a pair of Christmas socks. My husband received a beer glass and a pint to go with it last year. That went down well. This year, he got a crappy 'Santa lol jokes' booklet and a party popper. He was most displeased after forking out for a nice chutney range set and international tea assortment set.
What horrors have you received/seen someone receive?