Having just recently acquired a brand new Toshiba Satellite Z30-A-130 laptop and after booting Ubuntu 14.04 on it, one thing I immediately wanted to disable was the touchpad. It seems way too sensible and I keep touching while typing, taking the focus away. Turns out it wasn't super easy, at least until I figured it out.
The first obvious idea was to check the System Settings panel for Keyboard and Mouse hoping for a "disable touchpad" option but none was to be found on my fresh Ubuntu install.
$ xinput list
...didn't show the touchpad entry either, even though it was working alright. The idea was to disable it via CLI:
$ xinput set-prop [device number] "Device Enabled" 0
But having no device and hence no device number, I couldn't do it either. The final bit that led me in the right direction was:
$ synclient -l
Couldn't find synaptics properties. No synaptics driver loaded?
So, a bit more poking around and it turns out linux-kernel 3.13 may not be the best bet for driving these touchpads. Someone reported success with 3.17 and it does have indeed much better support. My days of recompiling infinite numbers of kernels everyday (by hand, mind you) were long gone and it's been a good few years since I last had the need to try a different kernel. But I quickly learned that Ubuntu has a kernel team and they wonderfully package every release in all .deb glory. They even package the -low-latency variant too, which I immediately chose over the -generic one. :)
$ wget http://kernel.ubuntu.com/~kernel-ppa/mainline/v3.17-rc7-utopic/linux-headers-3.17.0-031700rc7_3.17.0-031700rc7.201409281835_all.deb
$ wget http://kernel.ubuntu.com/~kernel-ppa/mainline/v3.17-rc7-utopic/linux-headers-3.17.0-031700rc7-lowlatency_3.17.0-031700rc7.201409281835_amd64.deb
$ wget http://kernel.ubuntu.com/~kernel-ppa/mainline/v3.17-rc7-utopic/linux-image-3.17.0-031700rc7-lowlatency_3.17.0-031700rc7.201409281835_amd64.deb
$ sudo dpkg -i *.deb
$ sudo update-grub
And presto. One reboot later and I now have full control over the touchpad, even from the system settings which makes sense as all that was missing was a proper synaptics driver.
Update 2014-10-04: Turns out linux 3.17-rc7, despite fixing the synaptics driver issue, is a bit quirky when it comes to the wifi driver, as the connection suddenly drops and won't reconnect. -rc1 seems to be OK and it's the first version to feature synaptics support for my touchpad, so that's what I'll be using for the time being.