Horace and the Doughnut Puzzle

Hungry Horace has bought a large doughnut to share with his friends at a party. Horace has invited eight people to his house, including Greedy Graham and Fat Freda. The doughnut has a hole in it like this:



Fortunately, none of Horace's friends mind how much they get, as long as they get something.

How can Horace cut the doughnut into nine pieces USING AS FEW STRAIGHT CUTS AS POSSIBLE?