Here's my current UNIX screen config. Since I'm sharing parts of my config with other people I'm sourcing a user-specific file at the end of the first config file:

that's my .screenrc

screen 0 zsh

defutf8               on
deflogin              off
startup_message       off
vbell                 on
nethack on
bell_msg        'Bell in %n'
altscreen off

termcapinfo xterm*|linux*|rxvt*|Eterm* OP

defscrollback         1000
shell                 zsh


sorendition 10 99 # default!

#idle 600 eval "screen cmatrix -o -f -u 9 -C red -s" "idle 0"

#caption always "%{w$SCREEN_CAPTION_COLOR}%?%-Lw%?%{kW}%n*%f %t%?(%u)%?%{w$SCREEN_CAPTION_COLOR}%?%+Lw"

################################### Alex
source ./screenrc-$USER

And that's the second part of the config which is user-specific:

autodetach on
defscrollback 5000

# Set messages timeout
msgwait 2
activity "Activity in %n (%t) [%w:%s]~"
bell_msg "Trouble in %n!"
vbell_msg "Beep Beep ..."
pow_detach_msg "BYE"

# Ctrl-PageUp/Down or Alt-PageUp/Down or Alt-left/right
bindkey ^[[5;5~ prev
bindkey ^[[6;5~ next
bindkey ^[[5;3~ prev
bindkey ^[[6;3~ next
bindkey ^[[1;3D prev
bindkey ^[[1;3C next

#scrolling
termcapinfo xterm* ti@:te@

multiuser on
# allow the following people full control
# addacl unki, lefant
#aclchg aledesma +rwx "#?"

# show a window list at the bottom of the
hardstatus alwayslastline

# not so beauty
#hardstatus string '%{= mK}%-Lw%{= KW}%50>%n%f* %t%{= mK}%+Lw%< %{= kG}%-=%D %d %M %Y %c:%s%{-}'

# nice one with clock, but causes much traffic (seconds)
#hardstatus string '%{= kG}%-Lw%{= kW}%50> %n%f* %t%{= kG}%+Lw%< %{= kG}%-=%c:%s%{-}'

# looks quite good - my fav
hardstatus string '%{gk}[ %{G}%H %{g}][%= %{wk}%?%-Lw%?%{=b kR}(%{W}%n*%f %t%?(%u)%?%{=b kR})%{= kw}%?%+Lw%?%?%= %{g}][%{Y}%l%{g}]%{=b C}[ %c ]%{W}'

# get info at
# http://www.delorie.com/gnu/docs/screen/screen_toc.html
# http://gentoo-wiki.com/TIP_Using_screen

If you want you can also put the entire config into one file....