SipXphone is the fully featured SIP Java softphone especially designed to work with IP PBX applications. You can manage this program from the web and it can also be remotely configured using sipXconfig. It is perfect for personal computer desktops and laptops. It also includes a great quality sound, a friendly and intuitive user interface and great functionality. It is very useful for travelers that want to have immediate connection with their office phones; it lets you travel with your phone book and all the functions that your office phone includes. You can also call from your Outlook account. Download the free version from this site.