calcurse is a calendar and scheduling application for the command line. It helps keep track of events, appointments and everyday tasks. A configurable notification system reminds user of upcoming deadlines, the curses based interface can be customized to suit user needs and a very powerful set of command line options can be used to filter and format appointments, making it suitable for use in scripts.
Geeknote is an opensource Evernote console client for Linux, FreeBSD and Mac OS X. Use it for system administration needs, creating notes, notebooks, sync your local directories with Evernote notebooks. Use the power of command line!
GNU nano is designed to be a free replacement for the Pico text editor, part of the Pine email suite from The University of Washington. It aims to "emulate Pico as closely as possible and then include extra functionality".
SC-IM is a spreadsheet program that is based on SC. SC-IM stands for Spreadsheet Calculator Improvised. 🙂