nymshifting
Practice of changing names in order to suit one's purposes (such as avoiding being identified or to adopt an identity). Typically done on-line in such as email adresses.
He's been posting to other lists as well, he's nymshifting all over the place.
nymshift
To change online identities, such as a handle or login name.
I thought I'd seen the end of Cypher's trolling, but he just nymshifted out of my killfile.