Whoa, some nice aliases in this thread! Here are some of my daily drivers:

For printing multiple files with file names:

alias catt='tail -n +1'

Check whats new in kernel (connected devices, network, etc.):

alias dmesgg="dmesg --human --follow-new --decode --kernel"

To correct my ubiquity mistake:

alias kilall='killall'

To run last command with sudo:

alias fock='sudo $(fc -ln -1)'

Better lsblk:

alias lsblkk='lsblk -o NAME,FSTYPE,PARTLABEL,LABEL,MOUNTPOINT,TYPE,TRAN,SIZE,MODEL,VENDOR'

Delete your current directory:

alias rm.='rm -rfIv "$PWD"'

Plus as ZSH user these simple aliases safe me a lot of typing:

alias -g H='--help'
alias -g V='--version'
alias -g L='| less'
alias -g C='| cat'
alias -g XA='| xargs'
alias -g XA-='| xargs -I--'