If you own a Symbian cellphone and if you're interested in Macromedias Flash Lite player, watch out! There is a .SIS-file around (the Symbian installer format) which pretends to be the Flash Lite player but which contains the Cabir worm for Symbian... This is ugly, so be careful. Obviously Macromedia don't ship that worm in their Flash Lite player.

More information on it on f-secure.com: http://www.f-secure.com/v-descs/skulls_d.shtml

I can just recommend anyone installing a .SIS-file to have a look for the signature of the file. If it's an unknown signature, it might be dangerous for your phone.