This includes Xinerama dual head support, so that you can use both the LCD and an external monitor in XOrg. This worked for me, on my Presario M2000 laptop running Ubuntu 5.04 (Hoary). See the PresarioNotes page for other hints.

/etc/X11/xorg.conf:

# default font stuff that Ubuntu added
Section "Files"
        FontPath        "unix/:7100"                    # local font server
        # if the local font server has problems, we can fall back on these
        FontPath        "/usr/lib/X11/fonts/misc"
        FontPath        "/usr/lib/X11/fonts/cyrillic"
        FontPath        "/usr/lib/X11/fonts/100dpi/:unscaled"
        FontPath        "/usr/lib/X11/fonts/75dpi/:unscaled"
        FontPath        "/usr/lib/X11/fonts/Type1"
        FontPath        "/usr/lib/X11/fonts/CID"
        FontPath        "/usr/lib/X11/fonts/100dpi"
        FontPath        "/usr/lib/X11/fonts/75dpi"
        # paths to defoma fonts
        FontPath        "/var/lib/defoma/x-ttcidfont-conf.d/dirs/TrueType"
        FontPath        "/var/lib/defoma/x-ttcidfont-conf.d/dirs/CID"
EndSection

# default modules that Ubuntu added
Section "Module"
        Load    "bitmap"
        Load    "dbe"
        Load    "ddc"
        Load    "dri"
        Load    "extmod"
        Load    "freetype"
        Load    "glx"
        Load    "int10"
        Load    "record"
        Load    "type1"
        Load    "vbe"
EndSection

Section "InputDevice"
        Identifier      "Generic Keyboard"
        Driver          "keyboard"
        Option          "CoreKeyboard"
        Option          "XkbRules"      "xorg"
        Option          "XkbModel"      "pc104"
        Option          "XkbLayout"     "us"
EndSection

Section "InputDevice"
        Identifier      "Configured Mouse"
        Driver          "mouse"
        Option          "CorePointer"
        Option          "Device"                "/dev/input/mice"
        Option          "Protocol"              "ImPS/2"
        Option          "Emulate3Buttons"       "true"
        Option          "ZAxisMapping"          "4 5"
EndSection

Section "InputDevice"
        Identifier      "Synaptics Touchpad"
        Driver          "synaptics"
# see /usr/share/doc/xorg-driver-synaptics/README.gz for options
        Option          "SendCoreEvents"        "true"
        Option          "Device"                "/dev/psaux"
        Option          "Protocol"              "auto-dev"
        Option          "HorizScrollDelta"      "0"
        # don't do anything for 1-finger taps
        # this didn't work for me so I disable this device instead
        Option          "TapButton1"            "0" # 0 = no action
        Option          "MaxTapMove"            "0" # disables 1-finger tap
EndSection

Section "Device"
        Identifier      "Intel-LCD"
        Driver          "i810"
        #Driver         "vesa"
        BusID           "PCI:0:2:0"
        Option          "VBERestore" "true"
        VideoRam        16384
        # MonitorLayout "pipeA, pipeB". I'm not sure what a pipe is...
        # LFP = local flat panel...
        Option          "MonitorLayout" "CRT,LFP"
        Screen          0
EndSection

Section "Device"
        Identifier      "Intel-external"
        Driver          "i810"
        #Driver         "vesa"
        BusID           "PCI:0:2:0"
        VideoRam        16384
        Option          "Display"       "CRT"
        Option          "MonitorLayout" "CRT,LFP" # put crt on pipe A
        Screen          1
EndSection


Section "Monitor"
        Identifier      "LCD"
        Option          "DPMS"
        HorizSync       30.0-71.0
        VertRefresh     50-160
EndSection


Section "Monitor"
        Identifier      "Philips 107S"
        VendorName      "Philips"
        ModelName       "107S"
        Option          "DPMS"
        HorizSync       30.0-70.0
        VertRefresh     50-160
EndSection

Section "Screen"
        Identifier      "Local LCD"
        Device          "Intel-LCD"
        Monitor         "LCD"
        DefaultDepth    16
        SubSection "Display"
                Depth           16
                # use "1400x1050" for a widescreen
                Modes           "1400x1050" "1024x768" "800x600"
                # use standard resolutions for non-widescreens
                Modes           "1280x1024" "1024x768" "800x600"
        EndSubSection
EndSection

Section "Screen"
        Identifier      "External Monitor"
        Device          "Intel-external"
        Monitor         "Philips 107S"
        DefaultDepth    16
        SubSection "Display"
                Depth           16
                Modes           "1024x768" "800x600"
        EndSubSection
EndSection

Section "ServerLayout"
        Identifier "Dual Head (Xinerama) Layout"
        Screen 0        "Local LCD"     0 0
        Screen 1        "External Monitor" LeftOf "Local LCD"
        InputDevice     "Generic Keyboard"
        InputDevice     "Configured Mouse"
EndSection
Section "ServerFlags"
        Option "Xinerama" "true"
EndSection

# note that enabling xinerama disables Direct Rendering...
Section "DRI"
        Mode    0666
EndSection