Another update from the X-funky-and-cool-front: With some Patches from Kristian Høgsberg, I got compiz running with aiglx.
For those who don't know: Compiz is a combined window/composite manager that was released together with xgl earlier this year. aiglx is another approach to get 3D-accelerated Desktops on Linux/Xorg.
I've merged the appropriate (very experimental stuff, big fat warning!) gentoo packages into my overlay. For all non-gentooers: You are on your own, but you can grab
Kristian's patches here.
Update: Kristian told me that
Fedora Rawhide users are also lucky.
You can get it with
svn co http://svn.hboeck.de/xgl-overlay
(It's still called xgl-overlay, although it should probably be named »various-funky-x-stuff« or so, but I was too lazy to rename it)
To install it, check it out like above, put the path into your PORTDIR_OVERLAY-var in make.conf. Then re-merge libdrm, mesa, xorg-server and compiz (all ~x86). You can also merge experimental libcm/metacity-packages (metacity with 3d-effects), therefore add xcomposite to your USE-flags and merge metacity-2.15.5.
To start compiz on aiglx (that means »normal« X):
LIBGL_ALWAYS_INDIRECT=1 compiz --replace --strict-binding move resize minimize place decoration wobbly cube rotate scale switcher zoom &
gnome-window-decorator
(replace plugins with anything you want, the LIBGL-var and strict-binding are required for running in aiglx, this should be automatically detected soon)
For metacity use:
USE_WOBBLY=1 metacity --replace
As before, there is still a package for xgl, so you now can try both.