Shane was maybe the second most important character on the show -- his death was the equivalent of Jerry being forced to brutally kill Kramer, which is why it was saved for one of the final episodes of the season. As such, it came as a shock to many viewers ... unless, of course, they'd seen the following ad on AMC's site a couple of weeks before:

E! Online
The screwdriver is for your ears during Lori's scenes.

Before the second season had even ended, AMC started promoting pre-orders for the Blu-ray box set of the same season on their website. Which is great and all, but take a closer look at the extras detailed in the description:

E! Online
"And don't forget to Wikipedia 'Michonne'!"

Wait a minute, "Shane's last episode"?! That's right: With three episodes still to go before the end of the season, someone at AMC carelessly spoiled the fact that Shane wouldn't make it to the next one.

Now, it's true that Shane also died in the comic series the show is based on, but they'd already deviated from the story by making him survive way longer than he did there, so as far as fans knew, he could have stayed alive for the entire duration of the show. Obviously, the auto-spoiler was followed by fan outcry, and AMC even released a statement claiming that the ad was unauthorized and that "the matter is currently under investigation."

And it doesn't help when NBC does the spoiling all by itself.

For example, one of the most anticipated events for U.S. viewers was Michael Phelps' return to the swimming pool. To celebrate Phelps' distinguished career, NBC Nightly News anchor Brian Williams opened the show immediately preceding the race by saying, "And while we try to be sensitive about spoiler alerts for our viewers, Michael Phelps got crushed in the pool today."

David Shankbone
"We know you want to be surprised. Sadly, we possess less than half the shits necessary to make that happen."

Then there was the NBC affiliate that warned viewers to mute their TVs if they didn't want to be exposed to any spoilers ... and then showed them this:

The Daily Show
"Oh, and if you don't want to see this, look away. Probably should have mentioned that before we told you to mute it."

But the worst example involves 17-year-old Missy Franklin, who went on to win four gold medals in her Olympic debut. Let's say you spend the entire day locked away in a cabin in the middle of the woods with no Internet connection and no phone, just to make sure you avoid all spoilers -- you go through the entire day, then you turn on the TV to watch Missy compete in the women's 100-meter backstroke event. You tune in just in time to catch the presenter announcing that the race is coming up after some ads ...

Daily Mail
"Normally I'd fast-forward the commercials, but something tells me I should watch these."

... and the first ad starts with the words "When you're 17 years old and win your first gold medal ..."

Daily Mail
"And now we take you to Missy's race, where she came in first and won the first place gold medal!"

Yep, NBC decided to air a Today Show promo featuring Missy's victory right before the competition she went on to win, giving away the ending to one of the most dramatic personal stories the Olympics had to offer. But hey, at least they didn't replace the entire event with Ryan Seacrest's face (that's reserved for more trivial stuff, like tributes to victims of terrorism).

And then you have what Amazon.com did with the Hunger Games series.

After the massive worldwide success of the first Hunger Games movie, Amazon decided to use Mockingjay (the final installment of the trilogy) as part of their advertisement for their new Kindle e-book reader: They plastered some billboards in Washington, D.C., with the first page of the book, shown within the screen of their big calculator-looking gadget. The problem? That page happens to give away the ending of the previous book, and the shocking twist ending of the upcoming movie, Catching Fire. Here it is:

Huffington Post
Thanks to the E Ink display, spoilering has never been so energy-efficient!

For those of you not well-versed in YA literature, Catching Fire ends when the series' protagonist, Katniss, learns that her home "town," District 12, has been bombed to shit, partly because of her actions -- that's the ending twist, the "Luke, I am your father" of the book. Had anyone at Amazon bothered to so much as glance at the page they were about to use in their ads, they probably could have guessed that it was something important. This was either a deliberate ploy to get attention, or an act of supreme laziness.

blog.abt.com
"There's a lot of books back there ... are we supposed to read all of them before we plaster it on a billboard?"

While Catching Fire was originally published in late 2009 (meaning that fans had three years to catch up on the story), keep in mind that those fans multiplied many times over when the movie based on the first book came out in March of 2012, which was only about a month before this ad went up. Those who decided to watch the movies before reading the books (or just stick to the movies) knew they had to be on the lookout for spoilers, but they probably didn't know this involved "not looking out the window."

Of all the reality TV cooking competitions currently on the air (way more than we ever thought possible), Top Chef was a pioneer of the industry: It was one of the first shows to combine the excitement of watching people cook food with the intrigue of listening to judges critique said food and the privilege of not eating any of that food. As one of Bravo's most popular shows, Top Chef has been causing food boners since 2006.

And occasionally literal ones.

So going into the Season 7 finale, the show's 1.8 million viewers were eager to find out which cook would walk away with the big prize. Would the winner be Kevin Sbraga, the cocksure-yet-courteous New Jerseyite? Would it be Angelo Sosa, the -- OK, fuck it, Kevin won. That was, essentially, how Bravo delivered the information to the show's fans when, hours before the last episode, they posted a spoiler-filled clip on their website that was clearly meant to be had as a dessert, not an appetizer.

The clip is a "reunion" segment with all the participants looking back on the season, but it begins with host Andy Cohen saying, "Before we get into anything, we have to congratulate the winner of Top Chef: D.C., Kevin."

eater.com
"Just to reiterate, in case the viewers missed it, Kevin Sbraga won the whole shebang. That dude, right there, gray shirt."

"Kevin," the host continues, "how surprised were you when Padma said your name in Singapore?" Probably about as surprised as fans were when they watched that clip expecting a harmless retrospective and got this. The clip then goes on to spoil other particulars from the finale, like Kevin being assisted by previous Top Chef winner Michael Voltaggio, or the guy who didn't win being assisted by who gives a shit.

eater.com
"And here we see *mumble* sucking."

Bravo pulled the video within a few hours, but it was too late: It was soon reposted by other websites, which started announcing the yet-to-be-named winner to foodies everywhere. Many a season finale soiree was ruined that day.