Baseball

Baseball is often referred to as America's favorite pastime.  A nine inning baseball game on average runs over 3 hours long, so a lot of time does pass during the game.  Many expressions from baseball have been transferred into common conversation.

To hit a Home Run, is to hit the ball over the outfield fence in fair play.  That would be to the right side of the third and left side of the first base line.  A home run scores one point for the team, if no one else in on base.  If the bases are loaded, with players on first, second and third base, that is a Grand Slam, scoring 4 runs.  So, if someone does well, and enjoys success, you might say, "He hit a home run."

On the other hand, a baseball player may fail completely to even hit the ball.  If a batter swings and misses 3 times, then he has struck out.  So, when somebody fails, you may say, "He struck out." 

There are other expressions connected to baseball, such as getting to first base, which means getting started with something, possibly a romantic relationship.

There are too many idioms derived from baseball to list here, and Wikipedia already has a good entry for it.

Low Hanging Fruit

Low hanging fruit is the expression often applied by marketing professionals for easy sales. Easy wins, gained without a great amount of effort.  In business planning it is a method of prioritizing tasks that may be addressed and solved quickly, to get them out of the way of greater progress to larger, more difficult goals.

Easy pickings is a related agricultural style idiom, as you may imagine.  In this case, easy pickings often refers to duping of innocent people, pick pocketing or a theft that was very easily executed.  I'd prefer to think of easy pickings as a successful yield and harvest in your garden.

The Last Straw

The straw that broke the camel's back is an idiom known to humanity worldwide.  Other languages often refer to a similar expression, "The drop that made the cup overflow."  The drop in a cup is a simpler experiment to reproduce, since very few of us have camels and large supplies of straw.  (Related, see also Half Empty or Half Full)

Shortened to, "That's the last straw!" the expression in American English usually refers to the final event that causes a failure, a breakdown.  Often it is thought of as the last of many events that build up and then breaks one's will or patience, causing an emotional reaction of anger or resignation.  At this point, the individual has "had enough" and is ready to give up on the problem.