CypherpunkThe cypherpunks comprise a informal group of people interested in privacy and cryptography who communicate through the cypherpunks mailing list. In its heyday, the list discussed the public policy issues related to cryptography, as well as more practical nuts-and-bolts mathematical, computational, technological, and crypographic matters themselves.
A coderpunks list, open by invitation only, existed for a time. Coderpunks took up more technical matters and had less discussion of public policy implications.
There is a short section about the cypherpunks in Applied Cryptography ISBN 0471117099, written by Bruce Schneier.
The term cypherpunk was coined by Jude Milhon as a pun to describe cyberpunks who used cryptography. Jude died recently.
The mailing list's best days have been behind it for some time, possibly peaking around 1997.