Connect to your PC using a standard phone line, synchronize data while you're traveling, or check e-mail and surf the Web--all from your Handspring Visor handheld with the Handspring modem module.
To set up the modem module, we inserted the included AAA batteries, removed the slot protector from the Handspring Visor, inserted the module into the Visor, connected the phone line, and ran the modem setup program. Installation was quick, easy, and intuitive, requiring only about three minutes.
To use the modem module, you'll need to install, set up, and run communication software. Unfortunately, the modem module doesn't come with software, so you'll have to download your own--a truly surprising and disappointing omission by Handspring. However, Handspring does make the process of locating software easy. We visited www.handspring.com, followed links to software, and downloaded a trial version of MultiMail PRO from ActualSoft. You may want to read reviews of communication software in your favorite handheld periodical to determine what software title is best for you.
MultiMail PRO comes with configuration settings for AT&T World Net, CompuServe, EarthLink, Netcom, Shore, MindSpring, and the IBM Global Network. With this software, connecting our Visor to the Internet to check e-mail was as easy as entering a phone number, account name, and password. However, we were not able to connect our Visor to an alternate ISP whose settings were not preconfigured. (Obviously, we cannot fault Handspring for the limitations of third-party software, but we do fault them for not including software at all.)
If you want to stay connected while you're on the road, the 33.6 Kbps modem module is a must-have accessory. --Mike Brown
Pros:

Easy to set up and use
Connects your Handspring Visor to the Internet via an ordinary phone line Cons:

No communication software included