I've also heard that it's considered rude to point your hashi directly upwards. Something about it signifying death or something?
Also, does anyone know where to set your hashi down once you've finished eating? I was struggling with this when I went to an authentic Chinese restaraunt recently.
That 'authentic' Chinese restaurent could not have been 'classy', otherwise a chopstick holder, a small 'pillow-like' stand would be provided on the right side of your bowl.
If none is provided, just lay it on the table next to the bowl or plate; however in familiar company (at home) it is alright to lay it on the rim of the bowl or plate or use the spoon as a holder.
About pointing it upwards, it applies to all "dirty" things; not just chopsticks; especially brooms. The sky is where the gods live and it would be considered disrespctful to point 'dirty' things at them.
The death part comes from it signifying joss-sticks used for praying in the temples and cemetaries.
I'll rather be happy than right, anytime.