Very simple and clear, yet incredibly powerful syntax. Especially easy management of lists and checkboxes. Very powerful support of tags and more complex attributes (especially "properties", which allow for database-like functionalities). An incredibly useful and powerful tool: Org-babel, which...
Mainly aimed at web developers, this web app can carry out all manner of "cyber" operations in a web browser. Change character encoding, regular expressions, compression, encode XOR or Base64, more complex encryption like AES, DES and Blowfish, creating binary and hexdumps and much more.