Eep! Apparently there are some who know not of SIGGRAPH's splendor. Because I find the niftiness of SIGGRAPH impossible to put into words, I resorted to Googlism to find the words I wanted to say.

SIGGRAPH is a (or rather, the) special interest group for computer graphics. It's an international organisation dedicated to the generation and dissemination of information on computer graphics and interactive techniques. It's the largest conference in the world for computer graphics and the quality is regarded as exceptionally high. Reps from ILM, Pixar, WETA, and more all flock to the annual conference, and the attendees revel in the coolness like a kid in a candy store.

Does that give a fair idea?