| Frogs and swastikas|
Before hopping on the Trump-train (at least, openly and overtly), Posobiec had a relatively small internet presence running a Game of Thrones blog called "Angry GOT Fan". He was also an intelligence officer for the US Navy for a time.
If Posobiec came to prominence for anything, it would have to be for peddling the bullshit Pizzagate hoax. At the beginning, he said he's never eaten at the pizzeria at the center of the hoax, and never even heard of the place until he read about from other wingnuts. In his initial "investigation", he livestreamed his experience on Periscope. During said livestream, Posobiec decided to start broadcasting a child's birthday party in one of the establishment's back rooms. The managers (understandably) thought this was creepy and inappropriate, and promptly kicked Posobiec and a friend he was with out. He was treated as a hero by the alt-right when the stream went viral. And thus, a hashtag was born. 
Rogue One=Anti-Trump propaganda?
In December 2016, Posobiec pushed the false story that the producers of Rogue One had edited the movie to add a scene that would have implied that Donald Trump was a racist. This, of course, prompted outrage from members of the alt-right (as well as other right-wingers) and Posobiec got the hashtag "#dumpstarwars" going around… despite the fact the Posobiec had virtually no solid evidence to back up his claims. It's about as ridiculous as it sounds.
Rogue One went on to have the highest Domestic Box Office sales of 2016. The boycott could not have been any more of a failure.
dox defense squad
In November 2017, not long after reports of Roy Moore having sexually assaulted teenage girls in the past came to light, Posobiec decided to defend Moore, and in doing so decided to take the classy route and dox one of Moore's accusers by posting her name and workplace on his twitter.  He later deleted the post, claiming he did it out of "respect" for the accuser.
Other notable wingnuttery
- Allegedly planted an infamous "rape Melania" sign at an anti-Trump protest in order to paint the protesters in a negative light.
- Posobiec tweeted that NASCAR races are never targeted for terrorist attacks because, according to him, NASCAR fans are armed. He was promptly ridiculed for this statement.
- Came up with a hoax that CNN defended Bill Maher's alleged use of the n-word.[note 1]
- The original article was about Trump's chances of invoking executive privilege.
- 2016 Yearly Box Office Results. Box Office Mojo.