Good Dualpane Browser, supporting all popular OS
Supports plugins from totalcommander.
http://doublecmd.sourceforge.net/

Ubuntu install:
sudo add-apt-repository ppa:alexx2000/doublecmd
sudo apt-get update
sudo apt-get install doublecmd-gtk

Arch Install

sudo pacman  -Suy
sudo pacman -S doublecmd-gtk