1. A method, comprising: receiving a sequence of one or more words optically or acoustically captured from a rendered document; identifying an electronic version of the rendered document based on the captured sequence of one or more words; selecting an advertising message by at least: identifying a keyword associated with the electronic version of the rendered document; determining whether the captured sequence of one or more words is located in the electronic version of the rendered document within a threshold number of words of the keyword associated with the electronic version of the rendered document; in response to determining that the captured sequence of one or more words is located in the electronic version of the rendered document within the threshold number of words of the keyword associated with the electronic version of the rendered document, selecting an advertising message related to (i) the captured sequence of one or more words and (ii) the keyword associated with the electronic version of the rendered document; and in response to determining that the captured sequence of one or more words is not located in the electronic version of the rendered document within the threshold number of words of the keyword associated with the electronic version of the rendered document, selecting an advertising message related to the captured sequence of one or more words; and providing the selected advertising message.