We have two hybrids chickens here. The first is our cockerel, Aramis, and we assume he is hybrid. We got him from a neighbour who was moving away and had no need for him. The bleeding hearts that we are we took him and set to work making a chicken house and finding him some females. We were later told he definately had Barnveldar in him, but I don't know if that is pure or mixed with something else. What we do know is that he is huge. I still haven't seen a cockerel as big as him. He also has some slight leg feathering, and huge spurs. He's a pretty good cockerel, looking out for his girls and spending a lot of time watching over them and leading them to good eating spots. He has only ever had an issue with us if the food has emptied without us noticing.
Our other hybrid is Brienne. When we had our first broody I wanted some dark brown egg layers. I had heard that Marans were good for dark eggs and eating so they seemed perfect. I ordered some online but what I ended up with was some eggs that were Black Copper Maran x Cuckoo Maran and Rhode Island Red x Black Copper Maran. We then had a black, brown and white chick hatch from those eggs. Brienne was the white and that shouldn't be possible with those genetics, so I doubt the seller's description! Despite her suspect origins, Brienne is a brilliant hen. She quickly became top hen (first or second day in the flock) and now lays nice brown eggs between 73g and 83g.