Well, this article.

#4 in the article states:

Not just lost, but in one critical battle, his [Xerxes'] entire army was humiliated by a grand total of 300 warriors who belonged to a weird military cult called "Sparta."

Oh again, the myth of the 300 warriors at the battle of thermopylae. Except for the fact that it's bullshit. A quick view at the "Strength" section of the page gives a MINIMUM estimate of 5200. Okay, they might have been referring to this:

Leonidas, aware that his force was being outflanked, dismissed the bulk of the Greek army and remained to guard their retreat with 300 Spartans, 700 Thespians, 400 Thebans, and perhaps a few hundred others, most of whom were killed.

Even so, it's not just 300 Spartans who supposedly "humiliated" Xerxes, there were at least 1100 others assisting them.

Later on in the article:

One story makes it clear that Xerxes's real enemy wasn't the Greeks, but his own raging, delusional ego. As he crossed the Hellespont, a waterway separating Europe and Asia now known as the Dardanelles, the waters surged up and destroyed the bridges his engineers had spent days building. In response, Xerxes thought it would be appropriate to throw chains into the river, and ordered it be given 300 lashes and branded with hot irons. As his men delivered his punishment, they were ordered to harangue the river. "You salt and bitter stream, your master lays this punishment upon you for injuring him, who never injured you."

Notice, how it's subtly mentioned that it could all just be a story. Cracked.com, however, attempts to pass it as proven, historical fact. Let's just view the related wikipedia page, shall we?

The bridges were described by the ancient Greek historian Herodotus in his Histories, but little other evidence confirms Herodotus' story in this respect. Most modern historians accept the building of the bridges as such, but practically all details related by Herodotus are subject to doubt and discussion.

He is then said to have thrown fetters into the strait, given it three hundred whiplashes and branded it with red-hot irons as the soldiers shouted at the water.

Emphasis mine.

Okay, so real talk: It could be true, maybe Xerxes was as egotistical as the cracked article has portrayed him to be. Then again, the accounts of Herodotus have been subject to much skepticism. If you're writing an article about what could be a mere story, it would be a good idea to also explicitly mention that. Omitting important stuff is tantamount to bad history.