My friend Andre recently started Rondee, a company offering free conference calling (although you do have to call San Diego). It doesn't force you to sit through ads before you get on the call, and it has some cool features:
- Register phone numbers with the service so you don't have to identify yourself every time you call in.
- Schedule calls via a web interface, and send out invitations via email.
- Export your calendar to iCal, Outlook, Google Calendar
I'm not spending 3 hours a day on conference calls like I was five years ago, but I still think this is pretty cool.