Yeah, I agree with Mr. UK over here on the cardboard issue. It's not to filter out the ickies, it's to keep the end of your joint from getting closed with spit. It's damn useful, and you can take bigger hits if you make it wide. My rolling papers made out of hemp =). I actually prefer mixing my weed with tea leaves if i'm gonna mix it with anything. I like to keep the tobacco and the weed separate. Tea adds a great flavor to it. Try it out. (I've used a blackberry green tea and a rose petal black tea for this. I've never tried anything else but those two work well.)