I have several different iDisks and wanted to create scripts to automatically mount each iDisk. Here's what I came up with, and it seems to work well. Copy and paste the following into ScriptEditor, and replace the references to username and password with your iDisk account information. Save the script with a unique name, and each of your iDisks is now a double-click away.

tell application "Finder"
  mount volume "afp://idisk.mac.com/username" as user name ¬
  "username" with password "password"
end tell

[Editor's note: In case it doesn't come out correctly, the symbol after "as user name" is the Script Editor's line break symbol, entered with option-return. The 'mount' command is one line; it's broken up here for narrower display width.]