If your work requires making a lot of phone calls, you may find this module extremely useful. Epesi can be extended by plugins to Asterisk, Skype, FreeCalls and other voice over IP technologies. Thanks to them you may call right from the contact window by one click (phone numbers with links). You may also set voice conferences with your coworkers, to improve coordination of work and save your time for writing messages or using phone during work.
Commercial Epesi License for Premium modules
MIT license for Epesi Core and CRM