Microsoft has launched two new programs that allow people to place calls from the Outlook email program.
The latest versions of Office Communications Server 2007 and Office Communicator 2007 add voice calling and video conferencing.
Users can now look at an email in Outlook can see whether the sender and other recipients are online and available to talk. Then, with one click, a user can invite the group to an IM chat, a call or a video conference.
Communicator, a desktop application, also shows users whether their contacts are online, in the same way an IM buddy list does.
Users also can see their contacts' presence on Windows smartphones and new desk and speakerphones that plug into Ethernet jacks or PCs.
Bill Gates said that these changes are "as profound as the shift from typewriters to word processing software".