Slightly biased as this is where I live, but Stoke Newington is great place to spend lazy saturday / sunday afternoons getting sloshed with friends. There are 10 + pubs within walking distance who all are great places for one reason or another. I'll pick out the White Hart for its huge beer garden...
Lisson Gallery is one of the most influential and longest-running international contemporary art galleries in the world. Since being founded in 1967 by Nicholas Logsdail, it has championed the careers of artists who have transformed the way art was made and presented.
This is a great, free and lesser known spot in London. A glass lift takes you up the side of st.Paul's cathedral right out onto the roof terrace of this shopping centre. A great view over London.
Quinto sells second-hand books. I spend a lot of time here and have found some inspiring books over the years, both at Quinto and the other shops on this road. Koenig Books on the corner is good for art books, too.