For all its problems and expense, the millions who use it daily is a testament to its convenience and (on a good day) its speed.

BBC: London Underground celebrations to mark 150 years

But it may do so at the expense of their attentiveness towards strangers encountered physically (rather than virtually) in daily life.

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These are the amounts deducted daily from mutual fund accounts, and it's a good idea to favor funds that have low expense ratios.

FORBES: How (And Why) To Open A 401(k)