Here's something! ...unity image effects. The only problem is that it requires Unity Pro. Good luck! ;)

Ok here's how I did it on the basic version:

1. Create a Sphere(or some imported model) and set its shader to Self-Illuminated, set a color if you want.
2. Create a particle and parent it to the light object.
3. Now Tweak the particle in the Inspector till you have a single particle slightly larger than the size of the lamp itself.
4. Create a second camera object and disable all its components except Camera, parent it to the main camera
5. Create a New layer called something like "LightGlow", Select the particle and assign it to the this layer
6. Select the new camera and in the Inspector change Clear Flags to "Depth Only".
7. Set its Culling Mask to the "LightGlow" layer.
8. Select the Main camera and in its Culling Mask, uncheck "LightGlow Layer"
9. Set the Secondary Camera's Depth to something greater than the Primary Camera's Depth.
10. This should give you a fairly decent looking light glow effect without using Bloom.

Note: If you want to get a better effect, Change the Texture for the particle and its color if needed. If there's a possibility of an object blocking the light, put it in the "LightGlow" Layer as well. This method does NOT require a light in the scene, everything can be lightmapped and make the light object appear to emit light.

Hope this helps...

I am following all the steps as written but my culling mask for the second camera is not working, second camera is putting glow on all the layers. Its behaving very strange, please put some light on it!!

Thanks! Angela