The fairly easy way to amaze people with your fancy flash drive! (for Windows)
Alright, first: You need some form of removable storage (not necessarily USB, but it's nice)
Now, insert the removable storage, and open a text editor (ie. notepad++ or notepad)
Step 2: Creating an Icon
icon="Your icon file here.ico"
Note: You can use icons embedded in a *.dll file by placing the dll file under the icon tag, and then icon index
ie. icon="shell32.dll, 5"
Bitmap (*.bmp) files are also supported for this action (but not recommended)
Step 3: Creating an auto execute command
Now, this is not necessary, unless you wish to have some app open.
action="Message to be displayed to describe app being run"
NOW, there are a couple options.
You could have the app only show up in Autoplay, or run when the device is opened from "My Computer"
open="App to be opened.exe"
Run on open from "My Computer":
shellexecute="App to be opened.exe"
Step 4: Creating Shell Commands
Alright, Shell Commands are little shortcuts that will pop up when you right click on the device in "My Computer"
shell\exampleshortcut=Description of app
You can use as many of these as you want, as long as the identifier is unique in each case (the "exampleshortcut" part)
Note: You can place and ampersand (&) before the desired character if you wish to have a keyboard shortcut for the command
Step 5: SAVE
Note: changes will not take effect until you eject, and then re-insert the device into the computer
Also: There is much more you can do with autorun files, but that's more advanced stuff about identifiers and misc stuff (not really that important)