Here are a few more often used commands, from a list I made for myself.
Lines starting with ------ denote commands that do not have a key-sequence
shorcut.



REMARKS: "ESC x"  is equivalent to "M-x".
	  All commands can also be invoked by "M-x (command-name)", but
		many have a key-sequence shortcut.
	  In general TAB and SPACE will complete (filenames, commands etc.)
		[in newer versions only TAB will do this]
	  Help is available through "C-h"


C-g		abort (within any command)
C-/		undo
C-x C-c		quit emacs
C-x C-f		load file
C-x C-s		save file
C-x C-w		write-file
ESC x shell	(or  C-x * e t  ?)
ESC v, M-v	page back
C-l		recenter
C-x 0		delete window
C-x 1		single window
C-x 2		divide window
C-x ]		forward-page
C-x [		backward-page
M-right, ESC f	forward-word
M-left, ESC b	backward-word
C-x C-b		list-buffers
C-x b     	switch-to-buffer
C-s (and C-s)	search forward: C-w completes the search string
				M-p selects previos search string, cyclically
				M-n selects next search string
C-r (and C-r)	search backward (& same as above)
ESC C-s		isearch-forward-regexp
ESC C-r		isearch-backward-regexp (C-2 2 C-r too!!)
ESC-<, C-home	beginning-of-buffer
ESC->, C-end	end-of-buffer
C-u 		repets a command
C-@, stop, insert, C-SPC	set-mark-command
C-x h		mark-whole-buffer
C-w		cut
ESC-w		copy
C-y		yank (paste)
C-x d		dired
C-x i		insert-file
C-x C-x		exchange-point-and-mark
------		print-region
M-C-v		scroll-other-window (also ESC C-v, M-next)
M-S-C-v		scroll-other-window-down
M-Home		beginning-of-buffer-other-window
M-home/M-end	beginning/end-of-buffer-other-window
M-u, M-l, M-c/C-x C-u, C-x C-l		case change word/region
C-t		transpose-chars
M-t		transpose-words
C-x C-t		transpose-lines
M-q		fill-paragraph
------		fill-individual-paragraphs
M-C-d		down-list (move forward down one level of parentheses)
M-C-u		backward-up-list (move backward out of one level of parentheses)
C-q 		quoted-insert (insert next character ad literam)
------		query-replace-regexp
ESC-%, M-%	query-replace:	replace, find next 	SPC
				replace, stay		,
				find next, w/o replace	DEL
				replace all		!
				back-up to prev. match	^
				exit			ESC
				enter recursive edit	C-r; exit C-M-c
C-n (whatever)	executes (whatever) n times (n=number, e.g. C-1 C-2 = 12)
C-k		kill-line, deleteline
C-x l		count-lines-page
C-x =		what-cursor-position
------		bibtex-mode  (for references)
------		what-line
------		delete-matching-lines
------		keep-line, delete all lines except those containing matches 
			for REGEXP
------		list-matching-lines
Esc $		ispell-word

        Mathematica (if the math.el package is installed)
        ===========

ESC RET		to execute a line (?)
ESC TAB, M-TAB	show completions
C-c C-v		math-remove-symbol
kill-math-cell		      	ESC k
math-copy-cell		      	C-c C-y
math-edit-function	      	C-c C-f
math-extra-help		      	C-h E, C-c E
math-help		      	C-h e, C-c e
find-math-error		      	goes to line indicated in the last "syntax error in" message
check-math-syntax
math-isearch-backward		backward regexp i-search, initialized to find In[...]:=
start-math			start Mathematica in current buffer

	TeXware (if not using AuCTeX)
        =======
-------		tex-mode/latex-mode
C-c C-v		tex-view  (starts an xdvi window)
C-c C-b		tex-buffer (starts 'tex' on the buffer)
			see also C-c C-r = tex-region
C-c C-f		tex-file (save all buffers & run TeX/LaTeX on current 
						buffer's file)
C-c C-p		tex-print
C-c C-l		tex-recenter-output-buffer
C-c C-k		tex-kill-job (kill the currently running TeX job)
C-c C-q		tex-show-print-queue
-------		validate-tex-buffer (check for paragraphs with mismatched $'s)
C-c {		tex-insert-braces (make a pair of braces and be poised to type inside of them)
C-c }		up-list (move forward out of one level of parentheses)