A car (and any other thing for that matter) is only worth what someone will pay. Our cars are now 15 years old, so the price will depend on the condition and in some cases the mods rather than anything else. You'll see people asking silly money for all sorts of stuff on eBay and the likes but whether they actually ever sell any of it is a different matter.
And just for the sake of the argument - realistically if I was to sell my scratched, dented, slightly rusty and stripped out 9 I'd be lucky to get £2.5k for it - it's certainly worth more in parts that whole!