I noticed a LOT of questions on the IRC help channel as well as on the Second Life Linux Help Area on how to run Second Life or OpenSim, which as of now, only have an up to date 32-bit viewer on Fedora Linux 64-bit. Since Second Life is a game with one of the BEST graphics available in the Linux environment, I can see why it is so popular. Here is a step by step guide on how to get it up and running on Fedora 16, 64-bit edition.
1. Install an OpenGL capable driver for your nVidia GeForce / AMD Radeon / Intel HD Graphics GPU.
2. Install 32-bit dependencies by:
a) Open a text editor like Gedit, VIM, Kate, etc. Paste this list in the text editor and save it as 'Fedora-ia32.txt'
arts.i686
audiofile.i686
bzip2-libs.i686
cairo.i686
compat-expat1-1.95.8-4.i686
compat-libstdc++-33-3.2.3-63.i686
compiz.i686
cyrus-sasl-lib.i686
dbus-libs.i686
directfb.i686
esound-libs.i686
fltk.i686
freeglut.i686
gphoto2.i686
gtk2.i686
hal-libs.i686
imlib.i686
jack-audio-connection-kit.1.i686
java.i686
lcms-libs.i686
lesstif.i686
libacl.i686
libaio-0.3.106-4.2.i686
libao.i686
libattr.i686
libcap.i686
libdrm.i686
libexif.i686
libgcrypt-1.4.0-3.i686
libgnomecanvas.i686
libICE.i686
libieee1284.i686
libsigc++20.i686
libSM.i686
libtool-ltdl.i686
libusb.i686
libwmf.i686
libwmf-lite.i686
libX11.i686
libXau.i686
libXaw.i686
libXcomposite.i686
libXdamage.i686
libXdmcp.i686
libXext.i686
libXfixes.i686
libxkbfile.i686
libxml2.i686
libXmu.i686
libXp.i686
libXpm.i686
libXScrnSaver.i686
libxslt.i686
libXt.i686
libXTrap.i686
libXtst.i686
libXv.i686
libXxf86vm.i686
lzo.i686
mesa-libGL.i686
mesa-libGLU.i686
nas-libs.i686
nss_ldap.i686
opencdk.i686
openldap.i686
pam.i686
popt.i686
pulseaudio-libs.i686
sane-backends-libs-gphoto2.i686
sane-backends-libs.i686
SDL.i686
svgalib.i686
unixODBC.i686
zlib.i686
b) Open 'Terminal' and do a 'su -' to switch to root user.
c) Run command '# for i in $(< Fedora-ia32.txt ); do yum -y install $i; done'
3) Download either Firestorm (recommended) or Second Life Viewer. Both will work although Firestorm is more popular due to more features and a more popular / user friendly interface.
http://www.phoenixviewer.com/
http://secondlife.com/
4) Install the viewer 'tar -jxvf FILENAME_VERSION.tar.bz2'

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If you are using OpenSUSE 12, 64-bit edition, installing either the official Second Life 32-bit viewer or the Firestorm 32-bit viewer is a lot easier. OpenSUSE 64-bit comes with 32-bit support already preinstalled!
1. Install an OpenGL capable driver for your nVidia GeForce / AMD Radeon / Intel HD Graphics GPU.
2) Download either Firestorm (recommended) or Second Life Viewer. Both will work although Firestorm is more popular due to more features and a more popular / user friendly interface.
http://www.phoenixviewer.com/
http://secondlife.com/
3) Install the viewer 'tar -jxvf FILENAME_VERSION.tar.bz2'
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If you are using Ubuntu 11 or Kubuntu 11, 64-bit edition, you will need to install 32-bit libraries to allow the official Second Life or Firestorm 32-bit viewer to run.
1) Install an OpenGL capable driver for your nVidia GeForce / AMD Radeon / Intel HD Graphics GPU.
2) sudo apt-get install ia32-libs ia32-libs-gtk ia32-libs-kde ia32-libs-sdl
3) Download either Firestorm (recommended) or Second Life Viewer. Both will work although Firestorm is more popular due to more features and a more popular / user friendly interface.
http://www.phoenixviewer.com/
http://secondlife.com/
4) Install the viewer 'tar -jxvf FILENAME_VERSION.tar.bz2'