Simple touchpad blocker for Linux. (Using synclient and notify-send)
You can have the touchpad blocker always to hand using a keyboard shortcut to call this script.
In Gnome 3 is simple: System Configuration >> Keyboard >> Shortcuts and create a new personal combination for calling this script
Make sure the key combination you use to call this script is an unusual combination not to interfere with the default keyboard shortcuts from other applications (e.g., is common to use ctrl + s to save a file, you shouldn't use shortcuts common keyboard)