Brain farts (or, things I do seldom enough that I always have to look them up)

brainfarts-bash.sh

# _EMPTY_STRING_
# The -n operator checks whether the string is not null. Effectively, this will
# return true for every case except where the string contains no characters. ie:
VAR="hello"
if [ -n "$VAR" ]; then
    echo "VAR is not empty"
fi
# Similarly, the -z operator checks whether the string is null. ie:
VAR=""
if [ -z "$VAR" ]; then
    echo "VAR is empty"
fi
# Note the spaces around the square brackets. Bash will complain if the spaces are not there.
# SOURCE: http://timmurphy.org/2010/05/19/checking-for-empty-string-in-bash/

# _KILL_PROCESS_BY_NAME_WITH_PS_AND_GREP_
kill $(ps aux | grep '[p]ython csp_build.py' | awk '{print $2}')
# SOURCE: http://stackoverflow.com/a/3510850/483260

brainfarts.debian.sh

# Unpacking a .deb file without root (i.e. without dpkg)
ar x somefile.deb
tar xzf data.tar.gz