Homepage of Enna: http://enna.geexbox.org/
Seems nice! And it has a repository for installing the Maemo 5 packages:

Maemo 5 Packages for Nokia N900
Enna is available for your favorite mobile phone. It comes optimized and pre-configured for your mobile to find all your possible multimedia contents. In order to install it, go to Package Manager and add a new repository:

* Name: GeeXboX
* URL: http://packages.geexbox.org
* Distribution: fremantle
* Component: main