Here's something that has to have originated in online culture, right? Nothing symbolizes the "lazily use as few keystrokes as possible" culture of the email/text message generation like combining punctuation to convey human emotions.
For example, this lets people know that there is a spider on your face and you are wearing a party hat.
Actually Been Around Since...
The first emoticon showed up nearly 120 years ago, when author Ambrose Bierce wrote his essay "For Brevity and Clarity" and proposed a new type of punctuation mark to convey jest, which he knew would make the satire a little more clear in typewritten correspondence where he proposed, say, killing a hobo with a bag of doorknobs.
The new punctuation took the form of a horizontal parenthesis, which was meant to look like a smile, sort of like a written laugh track to cue readers in on all the jokes.
This shit is fucking funny.