Am hoping to take the kids to London but on a budget. Can you recommend fun stuff that is either really good value for money or free? Would have loved to have taken them up the Shard or on the Eye but I just can't afford it so was going to take them on the Emirates Skyline instead - stuff like that.... ! Also any cheapy but tasty food recommendations. The kids love the tube so spending hours getting somewhere isn't a problem! Thanks. X