Coincidentally, have just hung out some of the birdfeeders we made at CenterParcs in September. Both are based on a mixture of seed and lard (lard is not melted, but must have been out of the fridge for ages, plus you mix it with the seeds with your hands so that softens it). #1 consists of this mixture put into a plastic cup, with a stick poked in the middle. It's been frozen since we made it, firstly so it would keep (September too early for fat for birds apparently), and secondly meant sure it came out of its mould nicely. It is now wodged in the fence looking like a big spotty lolly. #2 consists of a pinecone with a string tied round it, then lots of the fat/seed mix squodged into the gaps, and then built up into a ball.
Hopefully these will please our ungrateful local birds - they have left the monkeynut strings untouched, I think they may have been a bit too much like hard work.