In this post, the Netflix Performance Engineering team will show you the first 60 seconds of an optimized performance investigation at the command line, using standard Linux tools.
Just a list of 20 (now 28) tools for the command line. Some are little-known, some are just too useful to miss, some are pure obscure -- I hope you find something useful that you weren't aware of yet! Use your operating system's package manager to install most of them. (Thanks for the tips, everybody!)