A revised version of my ~/.exrc. Should be self-explanatory. 

"""ABBREVATIONS
ab #d #define
ab #i #include
ab #n #ifndef
ab #f #ifdef
ab #e #endif
ab #l #else
ab Attr Attributes
ab Appl Application
ab Vari Variables
ab Req Request
ab UNI Sapienza Universita' di Roma 

"""MACROS (KEYBINDINGS)

""Show help
map H :!$PAGER ~/.vi_help^M

""Write out file
map Q :wq!^M

""Reload config
map R :ex^M

" Go to top of file
map gg 1G

" Go to end of file
map G GA

""Read and append <cmd> stdout to next line, 
"" first white space
" previous/current file diff
map rd +:r!diff -u # %^M                   
" tmux buffer
map rb +:r!tmux show-buffer
" today date
map rt +:r{!}date +\%Y-\%m-\%d^M
" XA_CLIPBOARD
map rc +:r!xclip -o -sel clip^M
" sysinfo
map rs +:r!uname -rs^M

""Formatting
" indent lines
map gi :%!indent -i4
" reformat, wrap text at 72ch
map gf :%!fmt -w 72 %
" reformat paragraph
map gp :?^$?,//!fmt -w 72
" sort lines alphabetically
map gs :%!sort -u
" process file with hunspell
map gh :!hunspell -d en_US %         
" substitute patterns up to  current position
map gr :^,.s///g 
" remove leading tabs
map gl :%s/^[ \t]*//
" double space, whole file           
map gd :%!sed G                      
" expand TABS out in buffer          
map ge 'a!'bexpand
"comment lines in buffer             
map gc :'a,'bs/^/#/
" uncomment lines in buffer          
map gu :'a,'bs/# *//                 
" remove trailing spaces             
map gt :%s/ *$//

""Manipulating Buffers
" display vi buffers
map K :display buffers
" cut current line to buffer '1'
map C  "1Y$dd
" paste '1' after current position
map V  "1PASTE 
" mark current position as begin of new buffer
map # ma
" mark current position as end of new buffer
map * mb
" append new buffer to next line
map bv :'a,'b co .
" delete marked buffer 
map be :'a,'b del .
" move marked buffer to 'n' line
map bm :'a,'b mo .
" convert marked buffer to UPPERCASE
map bc :'a,'bs/.*/\U&/
" convert marked buffer to LOWERCASE
map bl :'a,'bs/.*/\L&/
" trim white space from marked buffer 
map bt :'a,'bs/[ ^I][ ^I]*$//g
" write marked buffer to file
map bw :'a;'bw

""TUNABLE OPTIONS
" Autoindentation
set ai
" Discard control characters
set bf
" Edit command-line history.
set cedit=\^[
" Store buffer on tmpfs
set dir=/tmp/run/1000
" Encoding
set fileencoding=UTF-8
" Case insensitive searches
set ignorecase
" Hide whitespace and EOL characters
set nolist
" show line numbers
"set nu
" Display a row/column ruler
set ruler
" Additional section boundaries
set sections=SeAhBhChDh 
" Shell env for ! commands
set shell=/bin/sh
" Show matching brackets
set showmatch
" Display current editor mode
set showmode
" Shift width in spaces
set sw=4
" TAB width in spaces
set tabstop=4
"expand tabs to spaces
set et
"soft wrap text
set leftright
" TERM type
set term=xterm-256color
" Verbose error messages
set verbose
" 72-N chars wrapmargin
set wl=72
"set columns=80
" refresh screen at typed char 
set redraw