In Portland, there are TONS of nude events. My personal favorite from this year was the Nude Bike Ride series. There were 3 or 4, but the largest was all throughout downtown Portland.... hundreds of nude cyclists and literally thousands of spectators crowding the sides of the street along the route.
Also, you are allowed to be nude anywhere in Oregon as long as you aren't sexually harassing anyone. Which honestly seems a little too open to interpretation to me, but whatever.
My favorite couple of nude hangouts are Collins Beach on Sauvie Island and Bagby Hot Springs, which is about 70 miles southeast of Portland.
GO NUDE - BE FREE!