One embodiment is a computer-implemented method for classifying documents in a collection of documents according to their intended readerships. The method comprises using a computer to select a document in the collection of documents; and using a computer to determine a characteristic of the selected document, the characteristic being: misleading when the document includes one or more features that are determined to be for a purpose other than reading the document; commercial when the document includes features that are presented for a commercial purpose; or personal when the document includes features of a personal opinion. The method further includes using a computer to classify the selected document as misleading, commercial, or personal according to its determined characteristic; and using a computer to repeat the steps of select document, determine a characteristic of the selected document, and classify the selected document for additional documents in the collection. At least some documents are classified as misleading, at least some documents are classified as commercial, and at least some documents are classified as personal. Other methods and computer program products are also disclosed according to even more embodiments.