True Conferencing is offering a free conference call trial — they're offering $30 free towards your first conference calls. There is no obligation for future conference calls or minimum billed usage, and there's also no contracts.
After you've spent the $30, the charge is 4 1/2¢ for audio conferencing and 5¢ for Web conferencing per minute per participant.
There's other conference call companies offering similar free trials, so I'd suggest trying out a few of them and compare their services.
