You can have a very good coffee at competitive price at the newly open icecream parlour Cremeria Vienna in Blackstock Rd, corner with Brownswood Rd. The icecream is delicious too.
Sophie, do try cafe vintage it's the nuts. it really is. I'm in there every day, its popular. I've seen Anish Kapoor, Nigel Slater and Tracy Emin in there amongst others. Its on corner of mountgrove road and finsbury park road.