Hellyeah

This is a Remote Administration Tool that is used by hackers to control
the victim's machine remotely. The possibilities of such application depend
on the needs of the attacker. The attacker infects the PC via the
e-mail or File and Print Sharing. A "server" allows him to connect via
a "client" on his own machine. The functions of a RAT may vary,
depending on the needs of the hacker. Some RATs can't really harm your
PC and the only purpose they were made for is hooliganism. But some
versions can steal vital information, remove files and even crash your
computer. The author of this pest is a hacker called Evil Unca HeLLfiReZ.
The RAT originated in May 2000.