The way C++ can do things with Internet Explorer, this can also be a great tool for makeing worms. DOS commands... you can do alot of stuff in dos. And in M$-WORD 97 you can attach code into a document. You can do alot of good and bad things in a PC. Nothing can totally protect you no matter what OS you have or how many patches you download.

Be paraniod! Thats part of the fun of being admin. over your own PC and/or network.