Are those devices dangerous? Of course they are dangerous, because, for example, a keylogger will send all letters typed by you on your keyboard, so they will be able to know your keywords.
If you want to keep safe your PC, install SpyRemover, a lite tool which can detect and delete more than 38,000 types intrusive devices.
While you have SpyRemover in your PC you will be sure that no one will access your computer.
SpyRemover is powerful and easy to use. It works with Windows 95/98/Me/NT/2000/XP.