That might be fun except now the dollar vs. the pound is so astronomically low that it's gonna be pretty expensive - especially since London is one of the most expensive cities in the world (esp. for accomodation)! Do you have someone with which to stay at all?
It is really bad rightnow, but the canadian dollar has always been low against the pind. I think as I travel to the UK a lot it doesn't bother me too much. I have a bank account in England where I keep some emergency cash too.
I plan on getting my brother to meet me in London, he'll shop whilst I watch gym and we'll party the rest of the time. Shring a room with him will half the cost. Plus I always buy rooms from priceline or hotwire as their prices are always about 50% of online hotel rates.
Hopefully this all works out, but if the economy gets really bad, who knows how tight we'll have to pull our belts in, fortunately in Canada our banking system is very sound and is not structured like many other countires. But we would be hurt by a further economic slow down in the US.