I know this is an old post however I will resurrect it :P

Traditional Rasta's exhale deep white smoke through the nose as the thc is absorbed rather nicely via the nasal membranes.

There is an example of this part way through the video "Mr.Nice"

[gvideo]http://video.google.com/videoplay?docid=4564833875003902181&ei=dSawSZqwBJK wqwKcsaGwAQ&q=Mr.Nice&hl=en[/gvideo]

I have tried and I think the onset of the effects are much quicker.