From what I can gather, the upper limit of senteo clickers that can be supported at one time is 60. I have opened other lines of inquiry as well, but so far info. seems to say one receiver per computer only, and the newest receivers with updated software etc. can support 60 clickers max. Someone I know is trying to set up a large scale demonstration with 200 participants and wants to be able to have audience participation. Will keep searching, but if anyone has heard of a way to make this possible, would love to know how.