procps (ps, top, vmstat, pgrep, w...)

As ps implementations go Linux procps is clearly the worst, as it documents essentially all of the stupid misfeatures of all other implementations in the man page, fails to implement some of them (like sorting on time fields), heuristically parses command lines to (unreliably) figure out what you really meant for overloaded and/or misused flags and arbitrarily forbids certain flag combinations based solely on their historical origins >20 years ago.

Thanks for Procps, it's wonderful!

Love this! Use it all over the www.askapache.com server

very useful