Ever find yourself on the road wishing that you could quickly check to see if a particular e-mail has come in? If so, a two-way e-mail device might just be what you need.

If you are an e-mail addict like me, two-way email devices offer the best fix for this constant craving. Three features make this a killer app. First, I can receive a copy of all the e-mails that come into my office e-mail box. Second, I can reply to and send e-mails using my company e-mail address. That way, contacts don't know that I'm not in the office when I correspond with them. Finally, these wireless devices feature an "always on" mode that lets me receive and send e-mails continuously. While these features may be available elsewhere, two-way email devices pull them together most effectively.

These devices are not perfect, though. Coverage can be spotty, much like a cellular telephone. Attachments cannot be opened as if you are at your desk. And unfortunately, this portable convenience comes at a price. The devices can set you back several hundred dollars and service costs range from $15 to $60 per month.

Without a doubt, the best of the bunch that I have tested is RIM's Blackberry. I have been using the 857/957 unit, which is a Palm Pilot-sized device. With a big screen and full keyboard, there is a ample room to view and create messages and the smartly designed interface is very intuitive.

My complaints have to do with the weak backlighting, which makes it hard to read messages in dim light. Also, I would have liked the keyboard to have orientation aids so I could tap out messages more discreetly.

I also tried the Motorola Timeport P935. The features I found most useful included the ability to compose a message and schedule when it should be sent, and the ability to respond to messages by choosing from a set of canned responses.

But the major issue I had was how outbound messages were handled. If a message could not be sent due to poor coverage, it would not keep trying. I needed to send the message again once I was in an area with better reception. In contrast, the Blackberry will keep trying to resend the message until it can go through.

Finally, there is the Motorola Talkabout T900. A pager-sized device, this was by far the smallest unit of the bunch. The small form factor makes it a smart choice for those who don't really expect to receive or send lengthy e-mail messages. But the major downside is that you can't send e-mails using your company e-mail address.

I know a product is really good when I drag my feet about returning it. To give you a sense for things, I have been dodging calls from the patient PR folks from these companies for months now. All I can say is that I'll be berry blue when they catch up with me.