Related:

• ig virus: n. A parasitic {meme} embedded in a {sig block}.
  There was a {meme plague} or fad for these on USENET in late 1991....
• ig quote /sig kwoht/ n. [Usenet] A maxim, quote
  proverb, joke, or slogan embedded in one's sig block and intended to convey something of one's philosophical stance, pet peeves, or sense of humor....
• ig quote: /sig kwoht/ [USENET] n. A maxim, quote, proverb
  joke, or slogan embedded in one's {sig block} and intended to convey something of one's philosophical stance, pet peeves, or sense of humor....
• ig block /sig blok/ n. [Unix; often written `.sig' there] Short for `signature'
  used specifically to refer to the electronic signature block that most Unix mail- and news-posting software will automagically append to outgoing mail and news....
• ig block: /sig blok/ [UNIX; often written `.sig' there] n.
  Short for `signature', used specifically to refer to the electronic signature block that most UNIX mail- and news-posting software will {automagically} append to outgoing mail and news....
• doubled sig [Usenet] n. A sig block that has been included twice in a Usenet article or, less commonly, in an electronic mail message.
  An article or message with a doubled sig can be caused by improperly configured software....
• No .sig is a good .sig
• I'm a mutated .sig virus. Copy me into your .sig or risk instant death.
• My .sig can't come out today. It has a virus.