A made up celebration. No such holiday has ever been organized. It's considered a meme on the internet that is mostly used by trolls, hackers, bigots. They would sometime relate the celebration to homosexuals despite 9/11 has nothing to do with any sexual orientation. They just use it to annoy and offend people.
You'll might see it on Youtube comments:

@Kidstylz
UR GAY
Tr0ll4lif3

@Tr0ll4lif3
Fuck you, dipshit!!!
Kidstylz

@Kidstylz
Gays love going to a 9/11 party
Tr0ll4lif3

@Tr0ll4lif3
WTF???
Kidstylz
by Qwame2000 January 22, 2012
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