Raspberry Pi "Always-on" Public Displays
There is one thing that hinders me every time I set up a permanently-on Raspberry Pi, and that's the screen blanker. The Raspberry Pi is quite power-efficient, and that's partly because it has at least three methods of blanking or turning off the screen after too much non-activity. Simply changing the screensaver setting won't stop it, there are other things that must be done. This post is basically a list of things you need to do in order to get the Pi to be a public display screen.
The Mouse Cursor
Firstly, as an aside, let's get rid of that pointer. Really simple, just install unclutter.
sudo apt-get install unclutter
This should hide the mouse pointer if there's no mouse plugged in, but if it fails, simply typing unclutter at a command prompt should do the job.
Disabling the Screen Blanker
Now the post proper. Firstly, you may need to install the following package
sudo apt-get install x11-xserver-utils
This is nearly always installed already, but it's always best to check. Next, open ~/.xinitrc (create it if it doesn't exist) and append the following lines
xset s off
xset s noblank
Next, open /etc/xdg/lxsession/LXDE/autostart (you'll need sudo to save it). Comment out (add a # to the beginning) the following line
# @xscreensaver -no-splash
And add the following lines to the end of the file
@xset s noblank
@xset s off
Now edit the file /etc/kbd/config (again, sudo is needed) and make sure the following options are set as follows
You'll need to find these options in the text, they'll already be there, just set at different values (BLANK_TIME will probably be set to 30, for example.)
Finally, open the file /etc/lightdm/lightdm.conf (sudo again), and look for the [SeatDefaults] section. Within this should be a line (probably commented out) with the option xserver-command. Uncomment it, and change it to read
xserver-command=X -s 0 -dpms
If there is no xserver-command option, create it. Now, reboot your Pi and it should never power off the screen again.