I did put an abandoned Raleigh Pioneer back on the road earlier this year. It had sat chained up outside the library with vandalised wheels all winter. I knew it was a decent frame and in good enough condition so worth of bothering with so I phoned and emailed the boys in blue and the council on several occasions to see what the procedure for claiming it was but I am still waiting for a call back/reply to my emails!
Eventually I asked the library staff who told me to take it with me and I'd be doing them a huge favour as they had been waiting for the past 6 months for the council to come and remove it.
Last month, I spotted 4 bikes (including an '80s 501 framed Raleigh in decent condition) lying on top of a skip and I knocked on the door and politely enquired and offered to buy them but the woman was incredibly rude and refused my offer so I guess they are in landfill now

).