free - Display amount of free and used memory in the system
egrep Search file(s) for lines that match an extended expression
pkill - Kill processes by a full or partial name
lsblk - list block devices
konsole - a versatile terminal. Integrates well with dolphin, a file manager.
echo - Display message on screen
open - open and possibly create a file
nice - control how much “running time” your program gets. See: nice --help
emacs - a text editor with an “operating system” built in. Extremely powerful and versatile editor.
(I just had to add this… 
)
screenfetch - Displays a bunch of system information.
history - history of commands 
yaourt - An obsolete AUR helper.
NOTE: Yaourt had been the most popular AUR helper, but it is not being developed anymore.
~ It’s all I could think of for “y” that hasn’t already been played. 
1 Like
touch - change file timestamps
hunzip - compress and encrypt dictionary files
pidof – find the process ID of a running program
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fdupes - a program for identifying or deleting duplicate files residing within specified directories.
strings - print the strings of printable characters in files
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sl - a steam locomotive runs across your screen.
2 Likes
lolcat - rainbow coloring effect for text console display
cal --y 2019 → shows full calendar of any year.
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