--- 
bash: |-
  !! - Last command
    !foo - Run most recent command starting with 'foo...' (ex. !ps, !mysqladmin)
    !foo:p - Print command that !foo would run, and add it as the latest to command history
    !$ - Last 'word' of last command ('/path/to/file' in the command 'ls -lAFh /path/to/file', '-uroot' in 'mysql -uroot')
    !$:p - Print word that !$ would substitute
    !* - All but first word of last command ('-lAFh /path/to/file' in the command 'ls -lAFh /path/to/file', '-uroot' in 'mysql -uroot')
    !*:p - Print words that !* would substitute
  
    ^foo^bar - Replace 'foo' in last command with 'bar', print the result, then run. ('mysqladmni -uroot', run '^ni^in', results in 'mysqladmin -uroot')
  
    {a,b,c} passes words to the command, substituting a, b, and c sequentially (`cp file{.bk}` runs `cp file file.bk`)
  
    Ctrl + a - Jump to the start of the line
    Ctrl + b - Move back a char
    Ctrl + c - Terminate the command
    Ctrl + d - Delete from under the cursor
    Ctrl + e - Jump to the end of the line
    Ctrl + f - Move forward a char
    Ctrl + k - Delete to EOL
    Ctrl + l - Clear the screen
    Ctrl + r - Search the history backwards
    Ctrl + R - Search the history backwards with multi occurrence
    Ctrl + t - Transpose the current char with the previous
    Ctrl + u - Delete backward from cursor
    Ctrl + w - Delete backward a word
    Ctrl + xx - Move between EOL and current cursor position
    Ctrl + x @ - Show possible hostname completions
    Ctrl + z - Suspend/ Stop the command
  
    Alt + < - Move to the first line in the history
    Alt + > - Move to the last line in the history
    Alt + ? - Show current completion list
    Alt + * - Insert all possible completions
    Alt + / - Attempt to complete filename
    Alt + . - Yank last argument to previous command
    Alt + b - Move backward
    Alt + c - Capitalize the word
    Alt + d - Delete word
    Alt + f - Move forward
    Alt + l - Make word lowercase
    Alt + n - Search the history forwards non-incremental
    Alt + p - Search the history backwards non-incremental
    Alt + r - Recall command
    Alt + t - Transpose the current word with the previous
    Alt + u - Make word uppercase
    Alt + back-space - Delete backward from cursor
  
    (Here "2T" means Press TAB twice)
    $ 2T - All available commands(common)
    $ (string)2T - All available commands starting with (string)
    $ /2T - Entire directory structure including Hidden one
    $ (dir)2T - Only Sub Dirs inside (dir) including Hidden one
    $ *2T - Only Sub Dirs inside without Hidden one 
    $ ~2T - All Present Users on system from "/etc/passwd"
    $ $2T - All Sys variables
    $ @2T - Entries from "/etc/hosts"
    $ =2T - Output like ls or dir
    .bash_profile = sourced by login shell, 
    .bashrc = sourced by all shells, 
    .bash_aliases = should be sourced by .bashrc
  
  Run something:
    for i in a b c; do $i 'hello'; done
  
  Do something on a bunch of files:
    for i in *.rb; do echo $i; done
  
  If syntax:
    if [ -e .ssh ]; then echo "hi"; fi
  
  file check flags:
    -e:  file exists
    -f:  regular file (non directory)
    -d:  directory
    -s:  non-zero file
    -x:  execute permission
  
  Avoid duplicates in your history:
    export HISTIGNORE="&:ls:ls *:[bf]g:exit"
  
  more here:
    http://www.linuxtopia.org/online_books/advanced_bash_scripting_guide/fto.html