We've got an old ikea sofa bed which Jimbo is threatening to take to the tip. It is very old, blue, and converts into a bed which is only comfy if you sleep on it with your head at the end furthest from the back. I bought it when I was a student, so it really is ancient.
Free to anyone who wants to come and help us lift it down the steps from our house.
Possibly try the freebies section on Gumtree, I've gotten rid of the most surprising items on there. Also make sure you take the ad down once you've got a taker otherwise you'll never stop getting emails about it!