CyberChef is a simple, intuitive web app for carrying out all manner of "cyber" operations within a web browser. These operations include simple encoding like XOR or Base64, more complex encryption like AES, DES and Blowfish, creating binary and hexdumps, compression and decompression of data, calculating hashes and checksums, IPv6 and X.509 parsing, changing character encodings, and much more.
The tool is designed to enable both technical and non-technical analysts to manipulate data in complex ways without having to deal with complex tools or algorithms. It was conceived, designed, built and incrementally improved by an analyst in their 10% innovation time over several years.
Online copy: https://gchq.github.io/CyberChef/
A free utility for Windows that extracts your wireless keys in case you forget them.
XML XPath development formatting correctness validation debugging extraction testing
A basic article on how to extract images from a .pdf file using the pdfimages utility from the package poppler-utils.
prose is a natural language processing library (English only, at the moment) in pure Go. It supports tokenization, segmentation, part-of-speech tagging, and named-entity extraction. Parses English text, can also natively extract e-mail addresses, hashtags, @mentions, URLs, and emoticons. Can tag segmented and analyzed text by part of speech, including punctuation marks. Can identify types of entities (people, places). Also has the option to build and train custom models.