Get rid of shaky touchpad pointer (cursor that jumps)

Recipe for Ubuntu 13.04
1. Open the file /usr/share/X11/xorg.conf.d/50-synaptics.conf and locate the block with Identifier "touchpad catchall".

2. Add the options next to MatchIsTouchpad "on" and the contents will look as follows:

Section "InputClass"
        Identifier "touchpad catchall"
        Driver "synaptics"
        MatchIsTouchpad "on"


        Option "VertResolution" "100"
        Option "HorizResolution" "65"
        # disable synaptics driver pointer acceleration
        Option "MinSpeed" "1"
        Option "MaxSpeed" "1"
        # tweak the X-server pointer acceleration
        Option "AccelerationProfile" "2"
        Option "AdaptiveDeceleration" "16"
        Option "ConstantDeceleration" "16"
        Option "VelocityScale" "32"
# This option is recommend on all Linux systems using evdev, but cannot be
# enabled by default. See the following link for details:
# http://who-t.blogspot.com/2010/11/how-to-ignore-configuration-errors.html
      MatchDevicePath "/dev/input/event*"
EndSection

3. Reboot

4. Open "Mouse and Touchpad" preferences window and adjust touchpad pointer speed.


Recipe for Fedora 18

1. Create file /etc/X11/xorg.conf.d/50-touchpad.conf

2. Add following settings to the file:

Section "InputClass"
        Identifier "touchpad"
        MatchProduct "SynPS/2 Synaptics TouchPad"
        Driver "synaptics"
        # fix touchpad resolution
        Option "VertResolution" "100"
        Option "HorizResolution" "65"
        # disable synaptics driver pointer acceleration
        Option "MinSpeed" "1"
        Option "MaxSpeed" "1"
        # tweak the X-server pointer acceleration
        Option "AccelerationProfile" "2"
        Option "AdaptiveDeceleration" "16"
        Option "ConstantDeceleration" "16"
        Option "VelocityScale" "32"
EndSection 

3. Restart gdm as superuser (you'll be logged out)

$ service gdm restart  

Reference:

https://bugs.launchpad.net/ubuntu/+source/xserver-xorg-input-synaptics/+bug/1042069