Lightgrep is a new regular expression engine, designed specifically
for digital forensics. Why another regexp engine?

Lightgrep:

  - searches for many patterns simultaneously
  - searches binary data as a stream, not as discrete lines of text
  - searches for patterns in many different encodings; give it dirty
    data, lightgrep don't care
  - never, ever, ever, never, never looks at a byte twice or backs up
    in your input

Lightgrep is still pretty new and doesn't have all the regexp features
you might be used to. But it has enough features to be more than a
toy, and what is supported is well-tested.