JUSTIN BIEBER MAY have fans in something of a tizzy today as he finishes his short Irish tour but crazed fandom is nothing new for the teen star.

Justin caused Oslo to come to a standstill when he visited there last year.

Tom Rise / YouTube

In fact this girl is a good example of the typical fan reaction Biebs causes:

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It can be very exhausting being a Justin fan:

Doug Peters/Doug Peters/EMPICS Entertainment

Mind you, the Justin Bieber fans aren’t the only ones who take it a bit far. Here is our list of the celebrities whose fans continually go the extra mile. Extra mile of mental.

1. One Direction

No prizes for guessing that one of the other tween-friendly pop sensations would have a big following.

This video of fans going on a One Direction stampede in Australia is sort of terrifying.

bubblesbuzz / YouTube

And this girl has taken her love of the guys so far she’s gotten One Direction nail art while shopping at a One Direction themed shop. Seriously.

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2. Lady Gaga

Gaga fans are called Little Monsters and will do anything to meet their idol. Even if means dressing just like her:

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Or just hugging one of her billboards.

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And there’s always the “jump on stage with your idol” move which doesn’t always go well:

lesliewbarnes / YouTube

3. Jedward

In case you felt that we weren’t pulling our weight in the fan stakes then there’s always Jedward.

Their fans are so bonkers that Jedward themselves film them screaming at them, probably in sheer disbelief about how loud they are.

JedwardTV / YouTube

4. Britney Spears

She may not be a “teen star” anymore but Britney Spears will always be responsible for the ultimate internet fan meltdown:

itschriscrocker / YouTube

And like Gaga, Britney has had her own scary fan run in while on stage. Eek.

cally1218 / YouTube

5. Beyoncé

If you thought you enjoyed Beyoncé at Super Bowl then wait until you see this guy:

LoveLautnerTaylor1 / YouTube

And this baby proves that Beyonce fans start young. Like, really young:

Andrea Dickerson Sinclair / YouTube

Although she might make you sing for her and as this fan proves, that’s actually a bit scary:

mtroux / YouTube

6. Michael Jackson:

Before Bieber, One Direction and even Britney were even alive Michael Jackson was making fans go absolutely wild.

In 1985 he caused chaos in London at the unveiling of wax figure of himself. You can tell it’s from  the past because the photo is in black and white.

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And, what is obviously the true marker of success, Michael also has a classic fan on stage moment. What’s great about this video is how he tries to slowly get away from her but just can’t for a good minute or so.

140shak / YouTube

7. Take That

Ah, kids today and their boybands and the like. Sure, they don’t have a patch on Take That back in the day.

They were so huge they’d sign autographs in pubs with their tops off. The 90s were mad.

Nick Tansley/Nick Tansley/EMPICS Entertainment

Like, really mad.

Nick Tansley/Nick Tansley/EMPICS Entertainment

And of course Take That came back and their audience are totally mature about it.

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Here they all are at a signing and it’s all very grown up but they’re still looking for a kiss off their fave Take That fella.

Some things never change.

TheCelebFactory / YouTube

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