Can I accelerate mouse sensetivity over the standard maximum?

I'm not really sure what the range of the mouse acceleration sliders are, but you can easily change this manually by using xset.

Try something like xset m 100 5, that makes it go very fast for me.

The syntax of the command is:

xset m <pixels to move when going fast> <pixels threshold before moving fast>

To make the changes stick, put them in your ~/.xinitrc

I do not know if this is the right approach, but changing the AccelerationProfile from 0 to 6 and setting the VelocityScale to 10 you can get a really quick pointer. Much faster than if you change it in "Mouse Preferences". Here's how to do it:

First, you need to find your mouse ID and ProductName :

xinput list
...
 Logitech USB Optical Mouse                 id=11   [slave  pointer  (2)]
...

Now you can set the AccelerationProfile to 6 with this command :

xinput set-prop 11 "Device Accel Profile" 6
# 11 = DEVICE_ID
# 6 = linear (more speed, more acceleration)

Then you set the VelocityScale to what suits you. (1 to 10) (Higher = Faster):

xinput set-prop 11 "Device Accel Velocity Scaling" 5

If the above solution works for you, you can make it persistent by editing your xorg.conf (/etc/X11/xorg.conf). Add this section at the end of the file.

Section "InputClass"
   Identifier      "Logitech"                   # Whatever you want.
   MatchProduct    "Logitech USB Optical Mouse" # ProductName from xinput list.
   Option          "AccelerationProfile" "6"
   Option          "VelocityScale" "5"
EndSection

Once you reboot, you should have the same result as with the xinput command.

Let me know if it helps.

*** Tested with Ubuntu 10.10 ***

References :