SHE (Super Hybrid Engine) is a technology created through the redesigning of hardware, software and BIOS and can bring an up to 53% longer battery life for the Asus Netbooks. In addition, the Super Hybrid Engine automatically manages and regulates power distribution based on usage requirements.
To be able to use the Super Hybrid Engine in Linux, you need an application (applet) such as Jupiter (along with jupiter-support-eee - this is required for Super Hybrid Engine support) which was designed for Eeebuntu, but works on other Linux distributions too.
But Jupiter is not just for the Super Hybrid Engine equipped netbooks. In fact Jupiter works with every laptop, desktop, or netbook computer regardless of brand. It can switch between maximum and high performance and power saving mode, change the resolution and orientation, enable or disable the bluetooth, touchpad, WiFi and so on.
Overall, Jupiter is a great application for any netbook / laptop and I strongly recommend it. I've used it on my netbook for a while and it does make a difference!
Note: I've found a small bug: when switching performance modes, don't go from the highest profile to the lowest, but instead go from Power Saver to High Performance and only then to Maximum Performance (and the other way around) or else Jupiter won't work until you restart the computer.
Download Jupiter .deb and .rpm packages | Remember to also download and install jupiter-support-eee if you own an Asus EeePC to be able to take advantage of SHE =) | Update: there is now a Jupiter Ubuntu PPA!
For a similar application, see Eee Control.
Special thanks to EmCH and Fewt from our UNE optimization post comments for the tip!