Multiple instances of the application

I wanted to run multiple instances of Skype but couldn't find a way to do it. Although I have polygamy patch for my MSN messenger, I couldn't find similar application to patch Skype. After searching the Internet, I came to know that there is a command line tool to run any application with different Window's user. The command is as below; runas /user: XXX application_executable For me, the solution was just adding one more user to Windows XP system(and assigning password to it too) and by firing following command; runas /user:new_user skype.exe I am not sure if this command works for other version of Windows, but it worked with my Windows XP professional. :-)