More on The October Surprise
Out of curiosity, I googled "October Surprise" and here are a few things I found:

1. Will Bunch, Phila Daily News, 5/6/08
Team Hillary warns of Obama "October Surprise"
This is what Harold Ickes, a longtime advisory to both Bill and Hillary Clinton, told Mark Halperin of Time's The Page tonight:

“We don’t know enough about Senator Obama yet. We don’t need an October Surprise. And (the chance of) an October Surprise with Hillary is remote.”

This remark is dismaying on several levels, partly because Ickes is virtually channeling Karl Rove, who implied something similar in a recent interview with GQ — not backed up by any information of course. Just planting this vague idea in Joe Average Voter's head that there's something about Barry (Barak) — pick your vice, political or personal — that all the kool kidz inside the Beltway know about, and it's going to pop one week before the election, is the only strategy here.

2. http://abcnews.go.com/Blotter/Story?id=5702697&page=1
Brian Ross and Len Tepper, 9/2/08
Is the McCain campaign afraid of an 'October surprise' involving vice-presidential pick Sarah Palin of Alaska? The Alaska state senator running an investigation of Gov. Palin says the McCain campaign is using stall tactics to prevent him from releasing his final report by Oct. 31, four days before the November election. 'It's likely to be damaging to the Governor's administration,'
said Senator Hollis French, a Democrat, appointed the project manager. . .

3. http://www.huffingtonpost.com/gary-hart/the-october-surprise_b_30086.html
Gary Hart, in Sept of 2006 (!) wrote:
"It should come as no surprise if the Bush Administration undertakes a preemptive war against Iran sometime before the November election. Were these more normal times, this would be a stunning possibility, quickly dismissed by thoughtful people as dangerous, unprovoked, and out of keeping with our national character. But we do not live in normal times. And we do not have a government much concerned with our national character. If anything, our current Administration is out to remake our national character into something it has never been.

The steps will be these: Air Force tankers will be deployed to fuel B-2 bombers, Navy cruise missile ships will be positioned at strategic points in the northern Indian Ocean and perhaps the Persian Gulf, unmanned drones will collect target data, and commando teams will refine those data. The latter two steps are already being taken.

Then the president will speak on national television. He will say this: Iran is determined to develop nuclear weapons; if this happens, the entire region will go nuclear; our diplomatic efforts to prevent this have failed; Iran is offering a haven to known al Qaeda leaders; the fate of our ally Israel is at stake; Iran persists in supporting terrorism, including in Iraq; and sanctions will have no affect (and besides they are for sissies). He will not say: ...and besides, we need the oil. Therefore, he will announce, our own national security and the security of the region requires us to act. . . Only an Administration inspired by pre-Enlightenment fantasy could believe a notion such as this. . . It does not involve much imagination to understand the timing. The U.S. is poised to adopt a Congressional regime change of its own in November. A political strategy totally based on fear can offer few other options to prevent this." (there is more that is worth reading).

4. http://www.adn.com/opinion/story/513084.html
by John Havelock, former Alaska Attorney General, 9/1/2008
"October Surprise" is a term used to describe a potential, external event that can control the outcome of a pending American election. We have had (so far) a mini October Surprise with the Georgia affair. Another may be coming up. The surprise scenario presumes the deliberate creation of a national security crisis by a small group of persons or even one person. Control over the American election may be purely incidental to the event or the surprise may be an effort deliberately focused on American politics. Either way, it is an "October Surprise" by consequence.

To take an obvious example, a terrorist group might schedule or postpone an attack depending on the group's assessment of its effect on a U.S. election. America is particularly vulnerable to the surprise scenario this year because, according to well-publicized polls, the uncommitted electorate currently perceives Sen. McCain as substantially more capable of dealing with a military emergency than Sen. Obama, while believing Sen. Obama to be far more capable of dealing with the country's domestic problems. Thus anyone, in or out of the country, in a position to precipitate an emergency with military overtones, has the capability of influencing the outcome of the U.S. election. . ." (more to the article, worth reading)