A term used to describe incriminating evidence found on one's computer relating this person to a serious crime. More specifically, suspicious searches conducted on Google only a few days prior to a crime.
For example, if a man was murdered by his wife, who poisoned him with sleeping pills, the "Smoking Google" would be the searches conducted by that wife for topics such as 'sleeping pills,' 'sleeping pill overdose,' 'poison pills,' [et cetera], obviously linking her to the crime. Smoking [Googles] are most commonly found by investigators and can be key pieces of evidence in a trial.
This term is most commonly used in place of the older cliche`, the "[smoking gun]." This term was recently used on the television show "In Session" by [Vinnie] Politan.