One way to approach this is to begin with what the ideal converged device might look like and then strip it down to make it as thin and cost-effective as possible - while still allowing it to be functional. Some of the characteristics of todays fat clients include:
Small (pocket-able; about the size of a larger PDA on the market today) with as large a screen as possible within the given form factor
GSM or CDMA cellular phone service with broadband (EV-DO or EDGE)
Mp3 playback (via broadband or memory)
Video playback (via broadband or memory)
Web browsing with full Java support
Popular OS allowing a wide-range of programs
Camera with video capabilities
GPS with full mapping capabilities
Bluetooth (file transfer, keyboard, headset, etc compatibility)
The cost for such devices is in the $700-$900 range. Over time, we can certainly expect the cost to drop, but the ongoing maintenance and replacement costs for such devices will remain substantial.
What if there was another way to exploit all of that content and transaction processing capability? What if we could develop devices so thin and cheap that everyone could afford one? Here are some of the characteristics they might have:
Even smaller form factor (comfortably pocket-able; about the size of a flip mobile phone), as large a screen as possible or preferable in that form factor
GSM or CDMA mobile phone service with Internet with broadband
Web browsing with full Java (or any open standard) support that makes email client, word processor, audio/video playback, etc. available without installing applications, which can be accessed directly from the Web
The technology is here to make these devices in these form-factors, so long as the remain open. Wide-area wireless network technologies, such as WiMAX, have the potential to drastically reduce the price of such devices. With WiMAX, companies (or municipal governments as they are now beginning to do) could blanket entire cities with Wi-Fi-like broadband Internet service.
This would not only enhance the always-on nature of devices, but could potentially render the entire mobile phone industry obsolete due to VoIP services. Devices would only need the Internet.