Express Talk VoIP Softphone- works like a telephone to let you make calls through your computer. You can call anyone on the internet who has installed it (or any other SIP softphone). Calls computer to computer are always free. You can also call ordinary 'real' telephone numbers anywhere in the world if you sign with a VoIP gateway service company
TouchCaller is another 'A la Touch' interface to display in a handy way your contacts. A cube is rotating to swap from page to another, and your contacts are directly token from the default database. No more import, like in PECaller (from the same DEV). Please, notice that you'll need a "fast" processor (DEV is talking about 400Mhz) and a DirectX compatibility
ZM Dialer is an application that will automatically dial the specified phone number, when you want, how many times you want, and for how long you want. Just drop the exe anywhere on the phone you like and run it
Disable AUTOMATICALLY (and prevent re-connection) data-calls (gprs, umts, hdspa, MMS, internet connection, wap connection) during roaming and restore AUTOMATICALLY data-call during normal phone state under home network
MissedCallReminder adds the missing "missed call" and "missed sms" reminder to Windows Mobile 6. The application can vibrate and/or generate a chosen sound at a set interval, to notify the user that there are missed calls or unread sms messages. It will wake up the device if needed to give the notification
SMSGiver - allows you to give your SMS phone number and rules/times to a person via SMS. Set your SMS phone number (and notes) in the options dialog. When someone wants to know your SMS contact number enter their phone number and tap the button to send it via SMS
gVo-Since Google hasn’t released an official Google Voice dialer for Windows Mobile, gVo could be your best variant. It's AssassinsLament who decided to make a Google Voice dialer for Windows mobile