London is an extremely expensive city, so if you're going out for drinks I suggest drinking in your hotel or hostel first, then going out. The pound to the dollar is alomst double...so that 8 pound drink is really $16 dollars. Although, logical drinking goes out the window with another tequilla shot. Also, if you're going from country to country, it is always good to think ahead. Buy a bottle (or two) of your favorite drink in, say Spain, before you head off to London. Another good tip- Always around hostels they are offering drink deals. Go during their "happy hour" and you will be happier having a little more money for the rest of your trip.