Which aliases do you find most useful or helpful to your Ubuntu experience?

Since first becoming an Ubuntu user I have developed a growing list of aliases, and there are some that I cannot imagine being without. This makes me think that there are probably still tons of aliases that I haven't thought to use which could make the lives of me and fellow ubuntu users easier.

What aliases do you guys use which are:
general - they apply to lots of users
helpful - you use them often or they save a lot of time when you do use them

Solution 1:

Here are some that I like:

#Opens current directory in a file explorer
alias explore='nautilus .'

#Opens current directory in a file explorer with super user privileges
alias suexplore='sudo nautilus .'

#Opens current directory in Ubuntu's Disk Usage Analyzer GUI with super user privileges in the background
alias analyze='gksudo baobab . &'

#Opens a GUI text editor in the background. Can obviously be replaced with your favorite editor
alias text='gedit &'
#Same as above with super user privileges
alias sutext='gksudo gedit &'

#Opens a file with whatever program would open by double clicking on it in a GUI file explorer
#Usage: try someDocument.doc
alias try='gnome-open'

#lists contents of current directory with file permisions
alias ll='ls -l -sort'

#list all directories in current directories
alias ldir='ls -l | grep ^d'

#self explanatory
alias ..='cd ..'
alias ...='cd ../../'

#show aliases
alias a='echo "------------Your aliases------------";alias'
#Apply changes to aliases
alias sa='source ~/.bash_aliases;echo "Bash aliases sourced."'
#Edit Aliases
alias via='gksudo gedit ~/.bash_aliases &'

Solution 2:

These are my preferred aliases:

alias ll='ls -lAbhc'
alias l='ls -lBohc'

#History search (use: hs sometext)
alias hs='history | grep $1'

#Sudo vim
alias svim='sudo vim'

#Add extra protection against mistakes
alias rm='rm -I'

#Unrar alias
alias unrar='rar e'

Solution 3:

The alias I use most often:

alias go=gnome-open