Ubuntu is a Debian-based Linux operating system, with Unity as its default desktop environment. It is based on free software and named after the Southern African philosophy of ubuntu (literally, "human-ness"), which often is translated as "humanity towards others" or "the belief in a universal bond of sharing that connects all humanity". According to some metrics, Ubuntu is the most popular Linux distribution.
There is an unofficial Compiz Plugin that allows you to move the Unity 3D (not Unity 2D) launcher from the left to the bottom.
Install the PPA - ppa:paullo612/unityshell-rotated
The packages to install are unityshell-rotated libnux-1.0-0
A new plugin Ubuntu Unity Plugin Rotated will be made available in CCSM
There is a likelihood of freezes on installation. If this occurs use CTRL+ALT+F1 to start a TTY, login and restart lightdm with sudo service lightdm restart.
Rerun ccsm to enable the new plugin
This plugin replaces the official Unity Plugin. You will obviously not receive further bugfixes from the Ubuntu development team - you will be reliant on the PPA maintainer to supply bug-fixes