Avatar: 1) One regarded as an incarnation, 2) An archetype or exemplar. Archetype: An original model after which other things are patterned; Exemplar: One worthy of being imitated, a model; 2)One that is typical, example. So what people have selected for their "avatar" can fit any number of the meanings of the word.
My avatar is a photo I took of a swallowtail butterfly that I took years ago while camping up in Flagstaff, AZ. The wingspan on that beautiful creature was at least 6" across and it was gracious enough to fly slowly, hover, and linger awhile to allow me to take a photo. I plan on creating a pattern of this butterfly for a wall-hanging. Haven't decided if I will do a needle-turn applique, or do a fused applique and then use Melinda Bula's Renegard Thread Play techique.