A few quotes about the Lisp programming language, from Paul Graham's website:
“Lisp is worth learning for the profound enlightenment experience you will have when you finally get it; that experience will make you a better programmer for the rest of your days, even if you never actually use Lisp itself a lot.” ~ Eric Raymond
“We were not out to win over the Lisp programmers; we were after the C++ programmers. We managed to drag a lot of them about halfway to Lisp.” ~ Guy Steele, Java spec co-author
“Lisp ... made me aware that software could be close to executable mathematics.” ~ L. Peter Deutsch
“The greatest single programming language ever designed.” ~ Alan Kay
“I suppose I should learn Lisp, but it seems so foreign.” ~ Paul Graham, 1983 (the joke being that he learned it and made a bunch of money using it)