just log in as root....
if you're using KDM, and can't log in as root, iirc you can allow root to login via the control center, under sys admin -> login manager
alternatively, you can open a terminal, su to root, then launch konqueror or whatever you need to. or just su then type "mkdir /usr/bin/xxxx" where xxxx is the dir name you want to create....
best not to use root more often than is necessary, of course.