Actually, no, according to Stephenson. From the appendix of my copy of Cryptonomicon:
"It has been pointed out that the word "Cryptonomicon" bears obvious similarities to "Cyphernomicon," which is the title of a Cyperpunk FAQ document by Tim May. This leads to the question: am I committing some form of plagiarism, or rendering homage, or what? The answer, strangely enough, is niether. I was completely unaware of the existence of Tim May's Cyphernomicon at the time I came up with "Cryptonomicon."
PS. Yes, I am the commenter previously known as anarky. No idea why that account got banned after a single comment.
Since anarky was hell banned after a single innocuous comment (unless there are things that were so awful they got deleted) it seems fair enough.
In 1995 there was Stephenson's short story in Wired about digital cash - "The Great Simoleon Caper".
Of course, the protagonists of Atlas Shrugged had renounced paper money and started using privately minted gold coins from Midas Mulligan's Bank way back in 1957.