Ahhh, thanks gsever - fortunately you can do the same thing in Maemo itself, no need for easy debian or other complex applications and methodology at all.

"Set Deb HW Keys" uses xbindkeys to run the command "wmctrl -r :ACTIVE: -b toggle,fullscreen" - it assigns this, as you said to ctrl + space (also ctrl + up arrow)

If you want to do this without mounting all the debian stuff, I've complied xbindkeys and attached below (if I get a PM or two showing interest then I'll make a proper deb file and add it to extras)

First thing you need to do, if you don't have one already is create /home/user/.xbindkeysrc and add:

Next, upload xbindkeys to /opt/xbindkeys/bin/xbindkeys (or wherever you want to) and then run...

/opt/xbindkeys/bin/xbindkeys -f /home/user/.xbindkeysrc

Now any time you hit ctrl + space it will toggle full screen on whatever the active window is at the time.