Some join just to keep tabs on rivals.

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Some were coding, others keeping tabs on the election, or just geek-gossiping.

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When Raytheon isn't busy building a railgun or tinkering with exoskeletons, it apparently spends some time coding software to help keep tabs on what folks are doing online.

ENGADGET

Although they may deny it, some New Hampshire voters have been keeping close tabs on the whole Iowa campaign.

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's Galaxy Tabs for no charge in premium cabins on some flights, including on 767s that don't otherwise have individual screens.

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The San Francisco company has only been offering mobile ads in earnest since April, and some companies buying Twitter ads said they haven't kept tabs on the effectiveness of their campaigns on mobile devices.

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Some professional traders have made it a part of their business to keep close tabs on what Icahn is eyeballing.

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Some text is overlaid on top of the cover photo, and a couple of tabs are condensed to make a more streamlined picture.

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In some cases, less paid home care is necessary because these monitoring devices permit keeping tabs on Dad part of the time, even if he lives alone.

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He was keeping tabs on developments in Uganda from his base in the UK. Whenever some prominent Ugandan businessman came to London to procure items for the government or the army, Ruparelia heard about it.

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