The term originated in science fiction fandom, originally simply used to describe the "ego boost" someone feels on seeing their name in print. As a reliable way for someone to get their name in print was to do something worth mentioning, it became caught up with the idea of voluntary community participation. As a result of this, in later years, the term grew to mean something akin to an ephemeral currency, e.g., "I got a lot of egoboo for editing that newsletter."
As a result of its prevalence in this context, it is often attributed to Eric S. Raymond. However, it has been in use in science fiction fandom since the 1950s, being referenced in the 1959 collection of fandom-related jargon Fancyclopedia II . It did not, however, occur in the 1944 predecessor to that work, Fancyclopedia I , suggesting the term came into common use sometime in the intervening years. The first print citation available electronically is Bob Tucker's 1954 Neo-Fan's Guide, where it is spelled "ego-boo" and a derivation is given from "ego-boosting activity"; later usage dropped the hyphen and blended the two words, a common feature of fannish jargon.
The earliest online citation recorded is a reference to it being used in 1982, describing InConJunction, a science fiction convention in Indiana; the high proportion of science fiction fans on Usenet, and the Internet generally, in early years no doubt helped spread it into the wider computing community.