[plug] X resolutions for presentations using a laptop

[Bill Kenworthy]

Using the ctrl-alt-+/- keys to switch resolutions in X magnifies the
screen in a virtual desktop in all versions of X that I have used. 
Instead, I need to be able to switch resolutions to so I can have a
normal desktop at each resolution.  Reading the X docs and trying a few
different setups has not allowed me to do this yet.

The reason is when I use the laptop for a presentation, I have to boot
it connected to the projector for X to start in the correct resolution
(usually 1024x768), or it defaults to the LCD 1400x1050 unless I edit
the config file for the session beforehand (preset the default to
1024x768).

Another more minor bugbear, is that switching between screens (i.e., LCD
and external) usually forces both to use the same resolution - the
1024x768 occupying the centre of the larger LCD.

Suggestions welcome!

BillK