From few days, I was bugged with the same old Gnome and its sluggish speed on Ubuntu. Wanted something faster or fastest X11Desktop Environment. As Linmaya and others commented in our habba discussions, LXDE has been great so far today. Its easy to install on Ubuntu box. Use the following command.
aptitude install lxde lxde-common lxde-settings-daemon
Once installation is over, Logout and change the session to LXDE. This will take you to the desktop on LXDE environment. All I need is more control on the theme and font sizes. Hope that will be taken care by the team soon.

LXDE
“Lightweight X11 Desktop Environment”, is an extremely faster, performing and energy saving desktop environment maintained by an international community of developers. It comes with a beautiful interface, multi-language support, standard keyboard short cuts and additional features like tabbed file browsing. LXDE uses less CPU and less RAM. It is especially designed for computers with low hardware specifications like netbooks, mobile internet devices (MIDs) or older computers. LXDE can be installed with distributions like Ubuntu or Debian. Applications running on these systems will run with LXDE. The source code of LXDE is licensed partly under the terms of the
General Public License and partly under the LGPL.
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