Still, these nagging problems should not overshadow the dramatic progress that women have made in recent decades.

ECONOMIST: Women and work

Unlike a subscription model, F2P players have no initial buy-in to keep them playing, no nagging guilt over not making use of that monthly fee.

FORBES: As 'World Of Warcraft' Bleeds Subscribers, Free-To-Play Is Already Winning The Future

What is nagging Europe's political leaders is not the text, which they grumpily signed up to last year, but the difficulty they are having getting it ratified.

ECONOMIST: The European Union

But when it became clear that Sven's men were not going to make life easy for themselves, the nagging fear of a Euro 2000 repeat began to loom large.

BBC: England fans suffer in ignorance

There was just something nagging at the back of my mind that he was not quite the Carl Froch that I have got to know over the past few years.

BBC: man on Froch-watch

But in the back of my mind was a nagging question: Does such transformative leadership produce superior financial results or not?

FORBES: New Research Cites How CEOs Outperform The Market -- Become A 'Transformative CEO'

But nagging questions remain: Why did a man who insists that he is not a collector (and gets miffed when called one) want a museum?

ECONOMIST: Compton Verney and the collector who isn��t