AIGLX enables accelerated indirect rendering in X.Org beginning with version 7.1. Drivers that work with AIGLX include: All Intel video drivers. Nvidia's beta binary drivers. The open source ATI drivers.
Archlinux's X.org package has AIGLX. So aside from installing X.Org you only need to properly configure it. Open xorg.conf and ensure the following modules are added: dri, dbe, and glx. You'll also want to enable the following options in their respective sections.
Section "DRI" Mode 0666 EndSection
Section "Device" Option "XAANoOffscreenPixmaps" EnSection Section "Extensions" Option "Composite" "Enable" EndSection