Acronym for "I Checked Google And The Memories". Indicates that the poster did the due diligence of 1. searching Google, and 2. looking through the indexed posts of the forum, and didn't find an answer, before posting a question. Seen almost exclusively in the Seattle LiveJournal Community.
Use of this acronym is a show of forum competency, and may reduce snark.
"Does anyone know of a good dog groomer in Wallingford that specializes in poodles? ICGATM." (fairly probably true)
"Hi I need a place to stay in Tukwila in November, ICGATM" (unlikely to be true)