Emacs!

$ emacs -q          # start with a different config file

C-;                     # iedit

C-x C-+                     # increase font size
C-x C--                     # decrease font size

C-x C-c                     # quit emacs
C-g                         # cancel
ESC ESC ESC                 # all purpose get out command
M-x                         # execute extended command
C-h ?                       # HELP
C-h t                       # tutorial
C-h r                       # manual
C-h k + keymap              # documentation on keymap
C-h m                       # help with the current mode
C-h v                       # help on variable name
C-h f                       # describe function
C-h i                       # read included manuals

C-v                         # scroll down
M-v                         # scroll up
C-l                         # clear screen (1x center, 2x up, 3x down)
C-p                         # prev. line
C-n                         # next. line
C-f                         # right
C-l                         # left
M-f                         # next word (forwards)
M-b                         # prev word (backwards)
C-a                         # move to the beginning of line
C-e                         # move to the end of line
M-a                         # move to the beginning of sentence
M-e                         # move to the end of sentence
M-<                         # beginning of document
M->                         # end of document

M-u                         # uppercase next word
C-u N                       # repeat next command n-times

C-x C-f                     # find a file

C-s                         # search
C-r                         # reverse search
C-s C-n                     # next item in search history
C-s C-p                     # previous item in search history
M-%                         # search and replace (y, n, q, ., !)
C-M-s                       # regexp search
M-x replace-regexp

F3                          # start recording macro
F4                          # stop recording macro
F4                          # play

M-x shell
M-x calendar
M-! shell-command           # execute a shell command
M-| shell-command           # execute a cmd and pipe into current region

# VCS
C-x v =                     # show diff of changes to current file
C-x v g                     # blame"
C-x v l                     # log of changes

M-x server start
emacsclient -t filename

M-x java-mode
M-x flyspell-mode           # minor mode: autospell
M-x follow-mode             # minor mode: one buffer -> two columns

C-x o                       # focus other window
C-x 0                       # kill current window
C-x 1                       # hide all other windows
C-x 2                       # horizontal split
C-x 3                       # vertical split
C-x 52                      # open a new frame
C-x 50                      # close a frame
C-M-v                       # scroll the bottom window
C-x 4 C-f                   # open a file in a new bottom window

C-x b                       # switch buffer (type ? for minibuffer)
C-x C-b                     # list buffers
C-x k                       # kill buffer

C-x s                       # save all buffers
C-x C-s                     # save buffer

C-x f                       # set auto fill column (interactive)
C-u 70 C-x f                # set auto fill column to 70
M-q                         # re-fill the paragraph

M-g g                       # goto line

C-SPC                       # set mark
C-x C-x                     # swap point and mark (= region)
C-u C-SPC                   # cycle through mark ring
M-h                         # mark region with current paragraph
C-x h                       # mark all buffer
C-x n n                     # narrow current region
C-x n w                     # widden current region
C-w                         # kill current region
M-w                         # copy current region
M-d                         # kill next word
M-k                         # kill to end sentence

C-y                         # yank (paste) last killed text
M-y                         # replace yanked text w. previously killed one

M-/                         # autocompletion

M-x try                         # try package
M-x describe-package
M-x package-refresh-contents

(previous-line N)
(setq var val)
(+ M N ...)
(tool-bar-mode 1)