IOS 4.2 allows Apple IOS devices (iPad, iPhone) to print using a new system called "AirPrint". Currently this is only supported by a few select hardware manufacturers, Apple's own printer simulator applications and printer sharing on Snow Leopard 10.6.5.
This document outlines how to configure CUPS and Avahi to allow printers to show up on IOS devices and allow printing to them. As a proof of concept cups-pdf was used to create a PDF of the printed document.
Addressbook Dialing Find the contact, select the number you wish to call. It's that simple!
With version 2.1 of AsteriskC2D for OSX you can try it out for 10 days, after which time you need to pay for a license key.
$30 for a single user license.
Dial from almost any Mac Application
Using the services Menu you can select any a number from almost any application and request your PBX to dial it for you. Don't forget to include the + in the selection for international dialing support!
If that's not enough for you, you can write your own bits to call the dialer application with the phone number and it will do the rest. Maybe a plugin for Firefox, or a widget, the possibilities are endless. If you do write stuff, please let me know so they can be added to the Plugins page.
Support for Asterisk and derivatives built in as well as thirdlane, Vonage, Fonality. Other PBX types can be added via a super simple plugin system.
Asterisk and SSL
If your Asterisk server is internet visible then you really want to look to secure it. Have a look at this document for details on setting your self up as a signing authority. This allows you to create a certificate which can then be signed and accepted by your users software.