It began quietly last summer when T-Mobile launched its Hotspot@Home service. "It" is the current skirmish in which mobile operators are seeking to annihilate the landline business of their competitors.

Last week, for example, Sprint followed rivals Verizon Wireless, AT&T and T-Mobile with a flat-rate voice plan costing about $100 per month. Sprint’s offering includes unlimited Web surfing, e-mail, text messaging, push-to-talk services and GPS navigation - services you pay extra for with the other carriers.

The all-u-can-eat voice alternatives are not no-brainers for large businesses, as discussed in the last newsletter. But the per-user fee can also be on the hefty side for many consumers, who are already getting free nights, weekends and mobile-to-mobile calling. (How much can you talk?)

Well, the moves likely represent the kickoff of a price-war-with-wiggle-room that doubles as a concerted effort to pull users off landlines and onto wireless networks. Speculation abounded last summer, for example, that T-Mobile’s Hotspot@Home service – which allows unlimited domestic voice calling over Wi-Fi integrated with fee-based GSM cellular service – was an attempt to woo wired telephony and Internet access users to an all-wireless setup.

And I’ve heard it speculated that AT&T and Verizon might eventually offer free landline services as an accoutrement to their wireless services, if for no other reasons than 1) doing so might circumvent their having to pay large settlement charges to telcos in rural areas and 2) current and emerging generations of users will likely choose wireless and mobility over landlines, rather than paying for both.

Now it will be difficult for businesses to get fiber-caliber services in the wireless access market. Still, some sites might begin swapping in cellular – or forthcoming WiMAX services – as primary links in small locations or as a poor-man’s disaster recovery service in others.

A telecom manager I know on the East Coast, for example, uses Sprint broadband (EV-DO Rev A) service in areas where DSL and cable services are either nonexistent or exorbitantly priced. The company’s primary carrier is Verizon Wireless, but because Verizon’s terms and conditions allow the carrier to limit data usage at will, this particular company uses Sprint — whose plan is truly unlimited – for the cellular disaster recovery application, which delivers nearly a T-1’s worth of bandwidth for under $100 per month.

Joanie Wexler is an independent networking technology writer/editor in Silicon Valley.