The thing is: there actually isn't any autoplay in flash drives. There's no place in windows to disable it, as windows shouldn't even support it.-jgpaiva
Actually there is a little bit of misinformation in this thread

All removable media supports "autoplay", since it is a windows thing and not device specific. No, "autorun" is a different thing, this is where automatically, through the file autorun.inf, a program is automatically run. Windows only supports this on CDROM devices, thus the emulated cdrom on U3 sticks. AutoPLAY is just windows saying "Hey, found a removable media that was just plugged in, what do you want to do?" and it presents you with the box that has items like explore and several programs you can run on the media based on what kind of data it finds on the media.
I have a 2gb Memorex U3 stick that I have had a few weeks and really like it a lot, I have several portable apps installed on the U3 launchpad and I use them. Not sure about Sandisk's implementation, but on my Memorex the only thing it ran by default was the Oddcast thing that tells you about it. You can specify apps that will autorun from the launchpad by managing the apps and checking the box to autorun them, but by default all mine were disabled.
Edit: Bleh, I even put the wrong autosomething in one place
