One thing that I learned about headlines in print publications is that you have to be careful about what individual deck of a headline reads, especially if the decks are a few words each. This rule apparently also applies to online journalism.
Brother of Irish running back
shot to death
That was the way the headline read on the index page of http://www.chicagotribune.com/ on Oct.31. The headline was listed among many others near the editorial pods, and at first glance, just blends in with the others. When I first read the headline, I only read the first deck and had two questions: 1) Who's Irish and why does that matter since the brother is probably Irish as well and 2) where is this brother running back to? It wasn't until I re-read the whole headline (a few times) that I understood that the brother of an University of Notre Dame football player was shot and killed. What also contributed to my difficulty of understanding the headline was Notre Dame's mascot/team names; while I know that they are the Fighting Irish, but the use of Irish in this headline first gave me the impression that it was a noun, which is why I interpreted running back as a verb.
While the splitting of the headline into decks can create ambiguity, puns, if used correctly, can make a headline memorable while still getting the message across.
Iowa tax on pumpkins is no treat
That headline is from http://www.miamiherald.com, and, from a list of about 10 stories, it was the headline I noticed almost immediately. The headline is clear and concise while still attention-getting because of the play on traditional Halloween concepts such as pumpkins and trick-or-treating. This play on words also makes the story more timely in that readers know immediately that the story will in some way relate to Halloween.
(headline list: http://www.miamiherald.com/news/nation/)