You can install from the maemo extras-devel repository:
Sources are available from svn at the project page. The current
package is built for OS2008. Both the N800 and N810 are supported,
although some features may not be completely implemented for either
libglade2 is required. Make sure you have it installed on your device
wmctrl is not required but can be extremely useful for dealing with
windows. A package built for the N800 is available here.
It is highly recommended that you are logged in via ssh when
installing powerlaunch for the first time, so if something goes wrong,
you can kill the program at any time. Warning: It is possible to
edit the config file in such a way to make it impossible to close the
program or make your device require a reflash!
The default install should be safe. Let me know if something is not
working as you think it should.
The default config of the program tries to emulate the default
systemui as closely as possible. So you shouldn't notice any extreme
differences right after the install (if you do, it's a bug). But the
real power comes in the customization which requires editing config
files (no editor UI at the moment). See the documentation for more information.
If you make a customization that you find useful, please send it to
me so I can incorporate it! Either prettier interface layouts or
config files for dealing with a particular task would be welcome.