A simple plasmoid for checking current ATI PowerSave state I have made because of my overheating Acer notebook :)
Version 0.2 will support power state switching!
# tar xzfv atips-0.1.tar.gz
# cd atips-0.1
# cmake -DCMAKE_INSTALL_PREFIX=/usr .
# make install (as root)
And of course you need ATI fglrx drivers with PowerSave support (through aticonfig)