In a little-publicized event last week, a good portion of AT&T\u2019s DSL customers in the Great Lakes states lost DSL service for a full work day. I was one of them.Don\u2019t worry. This isn\u2019t going to be a rant about network reliability or carrier customer service. Rather, we have to find the silver linings in any trouble-time, right?Like most people, I was concerned about responding to e-mails in a timely manner (which is about 2 minutes these days). So I assessed my options: Wait until the service was repaired (the repair status kept changing); go to Starbucks and enjoy a caffeine and pastry-filled work day; or try to use (hijack) a nearby wireless link that used a difference service.Although Option 2 was tempting, none of the options thrilled me. And then I remembered: I have a BlackBerry.For e-mail purposes, that\u2019s really all I needed to survive the outage and still be responsive to clients and colleagues. And that got me thinking about business continuity in the small branch of home office.Unlike headquarters or large regional facilities, redundant access lines from multiple providers simply isn\u2019t standard practice at small and home offices. Moving forward, I expect that some companies will, in fact, buy both DSL and cable modem service for offices that house key employees - and why not? For a relatively affordable price, redundant broadband lines would provide a high level of reliability.But for less than the cost of that extra broadband line, why not consider a wireless-enabled PDA service? For about $45 a month (with taxes), I receive unlimited e-mail and Web access regardless of where I\u2019m located. And for about $70, you can add a portable keyboard, resolving the slowed employee productivity that results from PDAs\u2019 tiny keypads.The benefits extend beyond just redundant landline access. Initially, we used mobility to justify our PDA rollout. We travel a lot, and mobile e-mail\/Web access is key to running a successful business.But the other benefit of a PDA is for backup in small and home offices. When voice also is effected by an outage, the PDA (if voice is enabled) provides that backup, too. And those using a hosted service can remotely configure (from the PDA) for calls to be automatically routed directly to the mobile device - avoiding missed calls.Nearly 80% of organizations support PDAs, such as BlackBerries or Treos, according to Nemertes' latest research. Although that may sound high on first glance, the penetration within the average organization is relatively low - slightly less than 3%. We\u2019re expecting that number to climb quickly and consistently as the lines blur between cell phones and PDAs.Providing your cellular network and your broadband access don\u2019t go dark at the same time (which is possible, of course), PDAs can provide nice backup for your small and home offices.