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Write comments to your history.
A null operation with the name 'comment', allowing comments to be written to HISTFILE. Prepending '#' to a command will *not* write the command to the history file, although it will be available for the current session, thus '#' is not useful for keeping track of comments past the current session.

Bash alias to output the current Swatch Internet Time
Output the current time in Swatch “Internet Time”, aka .beats. There are 1000 .beats in a day, and @0 is at 00:00 Central European Standard Time. This was briefly a thing in the late 1990s. More details: https://2020.swatch.com/en_ca/internet-time/ The alias is rather quote heavy to protect the subshell, so the bare command is: $ echo '@'$(TZ=GMT-1 date +'(%-S + %-M * 60 + %-H * 3600) / 86.4'|bc)

Connect to SMTP server using STARTTLS
Allows you to connect to an SMTP server over TLS, which is useful for debugging SMTP sessions. (Much like telnet to 25/tcp). Once connected you can manually issue SMTP commands in the clear (e.g. EHLO)

Advanced python tracing
Trace python statement execution and syscalls invoked during that simultaneously

Installing debian on fedora (chrooted)

Which processes are listening on a specific port (e.g. port 80)
swap out "80" for your port of interest. Can use port number or named ports e.g. "http"

Convert seconds to [DD:][HH:]MM:SS
Converts any number of seconds into days, hours, minutes and seconds. sec2dhms() { declare -i SS="$1" D=$(( SS / 86400 )) H=$(( SS % 86400 / 3600 )) M=$(( SS % 3600 / 60 )) S=$(( SS % 60 )) [ "$D" -gt 0 ] && echo -n "${D}:" [ "$H" -gt 0 ] && printf "%02g:" "$H" printf "%02g:%02g\n" "$M" "$S" }

create new branch from stashed changes
from http://git-scm.com/book/en/Git-Tools-Stashing Useful for when stash cannot be applied to current branch

Make sudo forget password instantly
By default sudo 'remembers' password for a few minutes, so that you do not need to re-enter password for a series of sudo commands that might follow within a short time duration. However, sometime you might want sudo to instantly 'forget' the password. (Next sudo command will need you to reenter the password) Credit: I first learned this while listening to one of the 'tuxradar' podcast.

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