The Sun made the easy quip & wrote "I wander (sic) what beer-swigging Lily will go as?
(Cock) Fosters perhaps?"
But I think that's too obvious. When she was in her beehive hairstyle days, she could have gone as High Barnet (although maybe she'll leave that for Amy Winehouse).
I wonder what her other musical & celebrity mates will go as? If she's friends with the Beckhams, Mrs Beckham could just go as herself. As could All Saints. Beth Ditto could be Wapping. There's an outfit for Russell Brand if he decided to dress a bit more soberly. The former Mayor could carry some weights and go as a station on the Bakerloo Line.
I'm sure the scope is endless. If you have any ideas for costumes or famous people you'd like to see dressed up as appropriate Tube stations, please let us know in the comments.