Internet Mimic

A variation of the Lickspittle, the Internet Mimic is someone whose adoration for an internet celebrity (sometimes a Small Name, Big Ego) results in them copying their speech patterns, writing style, slang, or general tone.

It's kind of like when your little brother or sister wanted to copy your hairstyle and listen to your music, except these people are probably twenty years old and ought to know better.

Comic Books

 * The Engine (www.the-engine.net), a forum run by Comic Book writer Warren Ellis, is full of these. They're the ones using nonsense compound words like "shiteyes" or "thoughtpeach", just like Ellis does in his wackier work. Also, they usually have a signature photo of them smoking a cigarette and trying to look moody or hard.
 * The Truth and Beauty Bombs message board (loosely centered around Dinosaur Comics, A Softer World, and The Perry Bible Fellowship) tends to imitate the grammar/punctuation eccentricities of Dinosaur Comics and its author, Ryan North. The imitation was more pronounced in the past, however.

Web Comics

 * Many users of the forums associated with The Order of the Stick use avatars in the creator's art style.
 * Mind you, most of these come from the forum avatar gallery. But then, a goodly amount does not - they're independent imitations. This diverges from the trope to an extent, because the users aren't mimicking out of adoration-it's simply a long running trend.
 * This trope also extends to the plethora of Web Comics on the forums. Many are posted as "at last, a non-OotS comic"- and are stick figure, heroic fantasy comics with slightly different facial styles.
 * It is often easy to identify an Achewood reader by their usage of "hella" "rad" and "dogg," or typing entirely in lowercase in order to make a downbeat statement.
 * Bluh!
 * 1 4M UNF4Z3D BY YOUR HUM4N BLUHS.
 * That is to say, with a comic primarily based on text, many fans of the comic will imitate a particular character's typing quirk (mostly the Trolls', which are more noticeable) to evoke that character's qualities, sometimes going so far as to use it to have impromptu role playing sessions.

Web Original

 * While not sort of the same thing, on YouTube Poop vids, be prepared for comments from users who do nothing but quote lines from the vid. Really, this applies to any Youtube video that's humor based, be it a clip from a movie, or a song ... in fact, anything with a spoken script applies here. If it contains a single funny or awesome line, the internet mimics will be all over it, saying nothing but that damn line.
 * On some 4chan boards, such as /tg/, it has in past been something of a fad to WRITE WITH THE CAPS LOCK DOWN in imitation of MR. RAGE. It got to the point where "MRS. RAGE" and "THE PROPHET OF FURY" turned up.
 * Some Zero Punctuation fans, especially on The Escapist forums, try to copy Yahtzee's Sophisticated As Hell style, often boiling down to them simply regurgitating whole phrases verbatim from his reviews. Yahtzee's thoughts on this? "What I do have a problem with is people (for this happens surprisingly often) who think the best way to impress me is to talk at me like we're at a fucking renaissance faire. What am I, a visitor from the magical kingdom of Faggotry?"
 * On GameFAQs's Current Events, the well-known troll Butters_1188 has his own mimic by the name of Dead Guy Hubbin. He absolutely adores Butters and makes multiple topics about his undying love for him. He also copies many of Butters' gimmicks, like doing a topic search for "Butters" and posting in every single topic that comes up in the results seven hours after the last post. He's even been seen copying and pasting many of Butters' topics from other boards. Plus he has the exact same posting style even when not talking about Butters. This causes many people to think he's Butters' alt.
 * Yu-Gi-Oh the Abridged Series is covered with this, arguably the biggest reason why the fanbase is now withering down.
 * Not even this website is safe. If there's a Yugioh example somewhere, expect it to have a line directly under it quoting the Abridged Series, relevant or not.
 * Noted right-wing troll Gary Ruppert on liberal snark site Sadly, No! has inspired numerous imitators.
 * The Angry Video Game Nerd is notorious for his fanbase which believes his Reviews Are the Gospel and constantly imitates his style in their reviews.
 * Raocow fans. Check the forums. Expect to hear a lot of "like it was no thing," "Charlie," "Freakin' Horse, and really strange non sequiturs.
 * It isn't hard to spot a regular Troper in an internet forum. Use of phrases or expressions common on this website but uncommon in the real world will work their way into posts with an improbably high density, revealing their true colors to any other Tropers who happen to be browsing the forum.

Miscellaneous

 * Without naming any names, there's an individual who bops around forums variously devoted to Magic: The Gathering, Dungeons & Dragons, birdwatching, British politics, and Furry Fandom who absolutely insists on making everyone think he is Michael Howard, MP. It takes all types...
 * Maybe Michael Howard does like Magic, D&D, birdwatching, British politics and Furry fandom?
 * The day any politician admits to having ties to the Furry Fandom is not coming for a long time.
 * Sports example: Strangely enough, St. Louis Cardinals' general manager Tony LaRussa recently had a mimic who set up a Twitter account with his name and pretended to be him. Many St. Louisans followed the account and genuinely thought that LaRussa was Tweeting. The account was finally found to be a fraud, but not before the mimic managed to Tweet something like this: "Well, we just played in Chicago and managed to come back without anyone dying or getting a DUI." LaRussa is now suing Twitter.
 * Hockey blog Down Goes Brown did the same thing with the Toronto Maple Leafs' general manager Brian Burke.
 * There are a lot of these on Twitter. Some are parodies (Kim Jong Il being the obvious example), while others are just creepy-obsessed.
 * Hunter S. Thompson impressions are very common across all forms of media.