For some reason it never occurred to me that you could use property() as a decorator. Of course, if you want to use getters and setters you can't, but for the (fairly common) case when you have a function that you want to turn into a read-only attribute, it works great:

class Foo(object):
    @property
    def bar(self):
        return <calculated value>

Huh. Seems obvious now.