In order to continue to be effective in my job as a code monkey, I constantly need to learn new things. That could either be enhancing my understanding of the technologies I already use or learning new technologies. Which ever it is, I'm always reading a book or a web site just to keep up.
I try to avoid getting bogged down learning dead end stuff which will probably mean that I am not learning something I really should be learning. Dead ends are unlikely to reward me for the effort and will probably result in my re-writing a substantial amount of code.