yes that is the receiver dryer. Maybe you are thinking about an Accumulator? Our Saabs don't have one, the reciver dryer takes its place. They both accomplish the same job (to capture moisture) but in a different way. GM cars typically use an accumulator (just to show that GM doesnt have all of its hands around Saab).
Thanks guys and yes my evaporator is leaking. It was leaking when I bought the car about 8 months ago. The guy said that it was too much for him to fix, and by your reaction I would say you agree. I'll look again for the evaporator in another picture. Thanks again!