18. A machine-accessible medium that provides instructions that, if executed by a processor, will cause the processor to perform operations comprising: selecting a plurality of N-grams from a second plurality of N-grams, wherein the second plurality of N-grams are associated with a range of values of N and the plurality of N-grams are associated with a sub-range of the range of values of N, wherein each of the second plurality of N-grams comprises a sequence of N bytes, where N is an integer; generating a statistical content classification model based on occurrences of the plurality of N-grams, if any, in a set of training documents and a set of validation documents; providing the statistical content classification model to content filters to classify content into one or more of a plurality of categories; determining a utility for each of the second plurality of N-grams using a frequency of occurrence of a respective N-gram in a subset of training documents of the set of training documents that have been classified in a respective category and a frequency of occurrence of the respective N-gram in remaining training documents of the set of training documents; and selecting the sub-range of values of N based on utilities of the second plurality of N-grams.
18. A machine-accessible medium that provides instructions that, if executed by a processor, will cause the processor to perform operations comprising: selecting a plurality of N-grams from a second plurality of N-grams, wherein the second plurality of N-grams are associated with a range of values of N and the plurality of N-grams are associated with a sub-range of the range of values of N, wherein each of the second plurality of N-grams comprises a sequence of N bytes, where N is an integer; generating a statistical content classification model based on occurrences of the plurality of N-grams, if any, in a set of training documents and a set of validation documents; providing the statistical content classification model to content filters to classify content into one or more of a plurality of categories; determining a utility for each of the second plurality of N-grams using a frequency of occurrence of a respective N-gram in a subset of training documents of the set of training documents that have been classified in a respective category and a frequency of occurrence of the respective N-gram in remaining training documents of the set of training documents; and selecting the sub-range of values of N based on utilities of the second plurality of N-grams. 22. The machine-accessible medium of claim 18 , wherein the set of training documents includes one or more electronic mail messages.