I am going to ask for one hour of your break.
Guy Steele has been involved in the design and implementation of programming languages for at least the last three decades. He is a Fellow at Sun Microsystems, and has helped shape the Common Lisp Object System (CLOS), Scheme, Java, and is now working on Fortress, Sun's parallel language for high-performance numerical computing.
He has both a homepage at Sun, and a Wikipedia page. The latter may, or may not, be a mark of greatness.
His talk, Designing a Language, was given at OOPSLA 1998. I saw this talk live when he presented it at Indiana University as part of a Horizon Day on programming languages. He speaks about the design and implementation of extensible programming languages using words of one syllable... unless he defines a multi-syllabic word in terms of one syllable words. It is amazing.
I highly recommend you watch this talk. You must listen carefully, however. Turn off the AIM and SMS, and think about what Guy is saying about languages and their design.