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Calculate pi to an arbitrary number of decimal places
Change the scale to adjust number of decimal places prefix the command with "time" to benchmark the computer (compare how long it takes to calculate 10000 digits of pi on various computers).

How many Linux and Windows devices are on your network?
Shows how many Windows and Linux devices are on your network. May add support for others, but that's all that are on my network right now.

convert ascii string to hex
Even adds a newline.

Get your external IP address without curl
Curl is not installed by default on many common distros anymore. wget always is :) $ wget -qO- ifconfig.me/ip

Find passwords that has been stored as plain text in NetworkManager

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"

save your current environment as a bunch of defaults

Show current pathname in title of terminal
This helps to keep track of what is going on when you have several tabs open in your terminal. The title automatically changes when you change directories.

Recursively list all of the files in a directory, group them by extension and calculate the average of the file sizes in each group
Here's an annotated version of the command, using full-names instead of aliases. It is exactly equivalent to the short-hand version. # Recursively list all the files in the current directory. Get-ChildItem -Recurse | # Filter out the sub-directories themselves. Where-Object { return -not $_.PsIsContainer; } | # Group the resulting files by their extensions. Group-Object Extension | # Pluck the Name and Count properties of each group and define # a custom expression that calculates the average of the sizes # of the files in that group. # The back-tick is a line-continuation character. Select-Object ` Name, Count, @{ Name = 'Average'; Expression = { # Average the Length (sizes) of the files in the current group. return ($_.Group | Measure-Object -Average Length).Average; } } | # Format the results in a tabular view, automatically adjusted to # widths of the values in the columns. Format-Table -AutoSize ` @{ # Rename the Name property to something more sensible. Name = 'Extension'; Expression = { return $_.Name; } }, Count, @{ # Format the Average property to display KB instead of bytes # and use a formatting string to show it rounded to two decimals. Name = 'Average Size (KB)'; # The "1KB" is a built-in constant which is equal to 1024. Expression = { return $_.Average / 1KB }; FormatString = '{0:N2}' }

Debug SSH at the Maximum Verbosity Level
When debugging an ssh connection either to optimize your settings ie compression, ciphers, or more commonly for debugging an issue connecting, this alias comes in real handy as it's not easy to remember the '-o LogLevel=DEBUG3' argument, which adds a boost of debugging info not available with -vvv alone. Especially useful are the FD info, and the setup negotiation to create a cleaner, faster connection.


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