Gloobus preview for Ubuntu etc

[#1]

Nice way of quick viewing files without opening an editor/viewer etc. Just press space on the file in nautilus
Web site http://gloobus.net/
Ubuntu forums link - http://ubuntuforums.org/showthread.php?t=828774

[#2]

Actually, if you don't use Gloobus, the space bar in Nautilus will cause the file to be opened with the default application.
Have you tried the split screen in Nautilus - press F3 for two independently navigable, side-by-side views.
Press F3 again to return to the standard display.

[#3]

True but if you just want a quick view of a file to check it is the one you want ... this is quicker than opening it in gedit even.