I have a small startup software consultancy, (www.phasepoint.net) and often times need to hold conference calls with clients. I was using the conferencing service provided by our telephone system, (www.Freedomvoice.com) but they were charging me 14 cents per minute per attendee. Last month I used 1300 minutes of conferencing and it cost me $112 (I get the first 500 minutes free each month); so I did a little research. I found two companies that provide free teleconferencing service.
Free Conference Call
FreeConferenceCall.com Reservationless Service
Maximum Number of Callers: 96
Maximum Length: 6 hours