Correct me if I'm wrong, but i was told that the regular memory sticks have the exact same pin configuration as the duos, but the duos are smaller and more expensive. if that is true, couldnt you just make a small adapter like the one shown in my poorly drawn picture to bridge the pin connections. I'm probably wrong about the pins because no one has made a small adapter, but i would really like to see the price i have to pay for a stick go down.
Yes, this is exactly what I thought of a while ago, although I don't have the means to test it out myself. If someone can rip apart a regular MS and a MSD, then maybe we'll be able to find out more about using regular memory sticks in the PSP.