Really interesting and eye opener talk by one of the greatest computers scientist of all times (in my modest p.o.v), Gerald Jay Sussman:
http://www.infoq.com/presentations/We-Really-Dont-Know-How-To-Compute
If I'm still a developer and still find programming an intellectual experiences is thanks to him. Lisp and Scheme make me discover that programming could be a really interesting experience. Maybe it's time to take a look at clojure 😉
