in a house or building or car that doesn't get good cell coverage? try one of these. It seems like nothing is for Nextel(Sprint) - sorry - get a new carrier.
wi-ex.com's zboost products, $99-$549
no nextel/iDEN supported.
Wilson Electronics Inc, specializing in long-distance Cell Signal Boosting
various antenna types, including the highly directional and highly signal boosting venerable yagi antennas. Not for NexTel. They have a 2W cradle booster for your car. one of them nearly "universal".
price depends on zipcode and size (sq. ft) of building. example: for 98674, 2500sq.ft $299. models available up to 50,000sqft. no wires to run that I see. I like this one, but I like Wilson better because it has Yagi antennas! They also have a version for businesses that do 2,500&5,000&25,000&50,000sqft. Residential version covers GSM Voice Services CDMA Voice Services, GPRS Data Services, EDGE Data Services, 1xRTT Data Services, UMTS Voice & Data Services, EVDO Data Services, HSDPA Voice & Data Services, Sprint PCS, T-Mobile voice & data.
Digital Antenna 60db Wireless Cell Amp & Repeater, available at cyberguys $547
this one requires a 50' wire to be run between the outside antenna and the inside small box/antenna. meant for RV's & yachts, homes, offices. Not for Nextel Phones.
Cellphone Signal Extender, available from thinkgeek $250-360
Choose the Right Model When Ordering! none of the models work with Nextel. You need to have at least 1 bar for the signal booster to work.
3W Cell phone Signal Booster, available from jdteck.com $215 (Network A 800/1900)
You should get 5 bars. I think you are supposed to run an antenna on the roof in a place where you can get some signal. works much better than the 1/2 watt thingies.