Brushing the surface of rocks with Curiosity's dust removal tool first enables the arm-held hand lens camera and X-ray spectrometer, in particular, to see features that might otherwise be obstructed.

BBC: Curiosity Mars rover deploys its rock brush

Three minutes later referee Paul Adams inadvertently obstructed a would-be tackler allowing Howley to dart from a scrum and spark a move which climaxed in a long pass by fly-half Paul Burke for left wing Craig Morgan to score.

BBC: Cardiff in the hunt

Federal prosecutors have at least considered a criminal investigation into whether the congressman obstructed justice by allegedly asking another woman who claimed to be his lover to lie about their relationship.

CNN: Condit passes private polygraph, lawyer says

Now initially the investigation was thought to be about who disclosed the agent's identity, but now there's speculation that it may be a probe into whether any government officials lied to the grand jury or obstructed the investigation.

NPR: Second White House Official Named in Plame Leak

What would-be Hall of Fame pitcher Roger Clemens could have or should have said before he allegedly obstructed a congressional inquiry with statements made under oath, and whether it might have prevented him from what is going on now, is obsolete.

FORBES: Clemens Could Pay Political Price for Business Success