The Developing City

There's a great exhibition on for architectural model geeks, in the Walbrook Building on Cannon Street. "The Developing City" has loads of models of some of the most recent developments in the city, and a large model of the square mile itself. 
 http://www.thedevelopingcity.com/about/  

An original model of the Lloyds Building. There is an amazing etched steel model of the Lloyds Building in the current British Design 1948 - 2012 exhibition at the V & A.

A model of the Walbrook building in the middle here, where the exhibition is. 

And here's the city model. The hard to avoid Shard in the foreground, natch.