Significance of Three Customs Involving String I've noticed three different customs involving string at Theravada temple service. If by chance anyone is familiar with the significance of any of these; it would be nice to know. The service is not in my native language so I miss a lot of nuances and end up forgetting to ask when I have a chance. 


The monks sit up on a raised area and occasionally seem to be winding string around various objects creating a web like display. What does this signify?
At times long pieces of string are sent through the group of lay followers and everyone tries to hold a piece of the string. What does this mean? 
At the end of the service people sometimes line up to receive a small string bracelet and a blessing from a monk. Is this just a nice gesture or does it have a particular meaning? Does anyone know what the blessing is for?


Thanks for any insights. :)
Chanting and good thoughts of the monks (even any other being) generate positive vibes. The string is used as a better means of conducting the vibration than may be air. (If you attach a tin to the end of two string and you speak into one you can hear the voice in the other.) Generally the string is wrapped around a vessel of water which cases the water to vibrate in tune with the chanting. These strings and water is given out as it the vibrations will carry some positive conditioning.