Help with shoulder flexibility

[echoes77]

Anyone with some suggestions for increasing shoulder flexibility? I am right handed so at the top of my backswing my left shoulder and the top of my left arm are very tight. I would like to take my arms back a little more at this point. The same can also be said for my right shoulder and arm at the end of my follow through. I recently got my hands on the Speedstick and swing it about 30 times a day to try to loosen the sockets and help flexibility. It has helped a little but I thought there might be some exercises to go along with this...thanks!

[Golfdog]

Lie on your back on the floor. Extend your arms straight up in the air so they are perpendicular to the floor. Make a fist with each hand and extend your thumbs so they point over your head. Now, with your arms extended fully, touch your thumb to the floor above your head. Do this with one arm, then the other. Do a reasonable number of these (I do sets of 15, but I have pretty good shoulder flexibility). It sounds stupidly simple, but you will definitely feel this in your shoulders.