For starters, you've got to be on EV-DO or WiFi, because 1xRTT (in addition to being ridiculously slow) would block incoming calls when active.

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Fair Isaac, a large fraud-detection firm based in Minneapolis, operates a system so fast that it can block dialled calls before they are even connected.

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Jammers also block incoming calls, which means that if used for an extended period you prevent anyone in your vicinity from hearing pressing, even emergency, news.

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The block of calls may have been tied to stock.

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Countries sometimes say they block Skype because its free or low-cost calls cut into the revenue of local phone companies.

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Later at the public safety press conference, Senators Joe Liebermann (I-CT) and John McCain (R-AZ) announced that they had, that day, introduced a bill in the Senate that also calls for the reallocation of the D Block to public safety and would provide funding using revenue from future auctions.

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In effect, though, the government, formed from a majority in the assembly, calls the shots, playing one chamber off against another to block anything introduced by backbenchers it does not like.

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