Virtumundo, is a worm often spread by USB stick or removable storages.
It seems it is not as dangerous as another trojans that steals sensitive data, though it's a worm.
It does the following;
. Displays advertisement pop-up messages
. Installs itself as Winlogon notification package
. The module get named randomly in /WINDOWS/SYSTEM32 folder
. Downloads softwares from remote servers
. Spread by USB or removable stroage devices with Autorun feature
Just watch your self with people randomly plugging in USB devices..
(SecureComputing)