According to an announcement by Sprint Nextel on Wednesday, the company start selling dual-mode 3G/4G wireless broadband modems for laptops beginning December 21. The laptop modem that will operate on both Sprint's 4G WiMax service, and the company's 3G cellular network. A Sprint spokesman said the company and its partners will eventually offer embedded dual-mode 3G/4G technology in other devices.

The first 3G/4G dual mode device in the country will allow customers to use the increased speeds of WiMax while in WiMax coverage, and switch to company's 3G network outside 4G coverage.

Priced at $149.99, the Sprint 3G/4G USB Modem U300 will come with a two-year subscriber agreement, after a $50 mail-in-rebate. Sunday onwards, the USB data card will be available through the Sprint direct business sales force, at most Baltimore-area Sprint stores and at select Baltimore-area retailers. Come January and the device will be available in Baltimore-area Best Buy stores also!

Within the Baltimore Sprint 4G service areas, the dual mode modem will access mobile multimedia applications at average downlink speeds of 2-4 Mbps. In places where Sprint 4G service has yet to launch, the device will operate on the Sprint Mobile broadband 3G network at average downlink speeds of 600 Kbps - 1.4 Mbps.

In a statement, Dan Hesse, Sprint CEO, said: "Sprint intends to be the leader in 4G and bring the wireless Internet to life. This first-of-its-kind device allows our customers to take the Internet with them essentially wherever they go by gaining enhanced speed and capability in 4G markets and the nationwide coverage of our 3G network across the rest of the country."