To create this monster build, Jamie used parts from 10 of the Big Ben sets (#10253), as well as a large number of Bricklink orders. So if you find the price of Tan elements has gone up, you know who to blame. The whole thing uses in excess of 50,000 pieces, and took 235 hours to build, which doesn't include the 25 - 30 hours planning time.
The finished MOC will be on display for the first time at this year's Bricktastic, 1-2 July in Manchester UK. If you can, go see it in person, but if you can't, click through to Jamie's stream on Flickr.