Background rendering with After Effects

There are several ways to run multiple instances of After Effects for AE background rendering:

• BG Renderer, script with UI at AE Scripts

• RenderQ, a free render queue for OS X

• AERender, an AE render droplet for OS X

• Command line controls are explained in AE Help, Automating rendering with aerender

There more on rendering via AE Community Help and in AEP posts tagged Background rendering and render (for example After Effects render tips and How to Optimize Projects in After Effects CS5).

Update: in comments Joost van der Hoeven notes Nucleo Pro 3 (compatible with CS5), an AE plug-in from GridIron [no longer developed].