See my Wikipedia contributions and techie tidbits (plus cat pics) on Twitter.

xy

ASCII line plotter, takes a CSV on the command line (or stdin) and emits a graph – repo/example website

tracehost

Network mapper using bash and GraphViz – repo/website

Have A Nice Day Trader

Trading strategy backtester – repo/website

tradeR

Currency analysis in R – repo/website

BIGO

Exploring Big ‘O’ programatically – website

Spectrum

Command line audio analysis – repo

DFT

Discrete Fourier transforms – repo