Not sure if this is exactly the correct area to ask this but ... oh well.
I've been playing 40K only since fourth edition, and the hundreds of dollars I've spent are now taking up valuable real-estate on my shelves. Other than using them for nerdy decoupage or else (equally tempting) setting them atop a funeral pyre of old tires and halogenated plastics - my personally signature to climate change - what use can these older editions be put to? What do you guys do with your outdated editions?