Martin Kozub , who has created the first Ubuntu-like skin for the Steam Linux client, has released a simple Skin Manager for Steam (obviously, for the Linux client) which you can use to install or remove skins.

Ambiance skin for Steam



Radiance skin for Steam

To use it, close Steam, then launch Steam Skin Manager from the menu / Dash, and select the skin to install: Ambiance or Radiance or install a different skin (here's an elementary skin ). You can also remove the skin that's currently in use.

Update: Steam Skin Manager can now get Steam for Linux to use native window borders. To get native window borders (re-download and re-install the deb below if you've installed a previous version), launch "Steam wb" from Dash / menu, instead of the regular "Steam" launcher:

Update 2: Steam Skin Manager now installs monochrome icons for Steam's new appindicator so it integrates with the Ubuntu Mono Dark / Light icon themes:

Download Steam Skin Manager

(deb - available for Debian, Ubuntu, Linux Mint, etc.) (deb - available for Debian, Ubuntu, Linux Mint, etc.)

Steam Skin Manager comes with two skins by default: Ambiance and Radiance which make Steam look close to the default Ubuntu themes. Using them, you'll get Steam to use the Ubuntu font, thin scrollbars, Ubuntu (Humanity) back and forward arrows, native-looking window buttons displayed on the left and other tweaks. Also, the font should look better using one of these skins.Arch Linux users can install Steam Skin Manager via AUR For manual skin installation instructions, see: Steam For Linux: Download The First Ubuntu-Like Skin