On the site, Gates takes questions from kids.
QUESTION: "I read in a newspaper that in l981 you said '640K of memory should be enough for anybody.' What did you mean when you said this?"
ANSWER: "I've said some stupid things and some wrong things, but not that. No one involved in computers would ever say that a certain amount of memory is enough for all time."
Gates goes on a bit about 16-bit computers and megabytes of logical address space, but the kid's question (will this boy never work at Microsoft?) clearly rankled the billionaire visionary.
"Meanwhile, I keep bumping into that silly quotation attributed to me that says 640K of memory is enough. There's never a citation; the quotation just floats like a rumor, repeated again and again."