As an owner of dreads and a dreader (though I did not do my own)
I think they're a great idea, contrary to belief, spiders do not grow in them and they are low maintenance and pretty clean.
I learnt how to do it in this website:
http://www.beautifullychaotic.net/howtodedread.html
Bang! it's very useful, and yeah, I'll just stop posting in dead threads....