The front lawns have played host to a giant toilet to draw attention to global sanitation issues. People have dressed as fluffy cows to try and ban live exports. They have turned up with their dogs, horses, bees and alpacas to promote other agricultural causes.

A man had a bath in olive oil to promote the plight of olive oil growers. Another individual with a blow up reefer came to … hang out.

So at first glance, the small group of life-sized white thingies, dancing about in the rain on Thursday was nothing to write home about.

On closer inspection, the scene involved a handful of young women dressed as tampons, complete with blue string tails.  And despite the miserable weather, they were having a great time – grinning as they leapt about, holding signs like, "Don't put the PM in PMS, Mr Abbott" and "Free hugs for tampon tax repealers".

Those white thingies have been dominating the post-budget debate this week.

You can bet your bottom buck that when Joe Hockey was bracing for his solo Q&A appearance on Monday, he prepared for every scenario imaginable – from vulnerable pensioners, to curious small business owners and angry parental leave takers – but not feminist students bearing a petition about the GST on women's sanitary products.

Hockey's pained "why me?" look and fumbling answer will go down in the annals of gawky MP moments.

"It probably should, yes, the answer's yes," he offered (subtext: I'll say anything if you just stop asking me about tampons!), when the ABC's Tony Jones pressed him on whether the GST should be removed on sanitary products.

Given that Liberal and Labor governments have been resisting a change to the tax on tampons and pads for years, it came as a surprise – perhaps even to the Treasurer himself – that Hockey all of a sudden announced a new position.

The next day, Tony Abbott certainly had an air of the astounded about him. While Hockey pledged he would take the tampon change to a treasurers' meeting in July and tasked his own department with costing the move, the Prime Minister tried to palm it off as a states-only issue.

But apart from the PM-Treasurer split – and the small irony of the Coalition becoming a sanitary products crusader less than three weeks after announcing cuts to the PPL – something else was brewing.

First, there was the simple fascination of watching male MPs, to see if they were "brave" enough to say tampon – and not just fudge it and say "sanitary" or "health products". And the whoop when Bill Shorten finally uttered the t-word in Parliament (it took him two question times).

There was also the rare opportunity for information exchange. In my office, talk turned to the cost of tampons and pads. There was genuine surprise from some male colleagues when they learned women need more than one of the items a day.

It's easy to underestimate such a conversation, but it's actually quite seismic.

This week, sanitary items went from something that not even women like to talk about between themselves, to something that men and women were openly chatting about in the workplace. And not feeling weird about it at all (or at least, not that weird).

For Sydney student Subeta Vimalarajah, who asked Hockey about sanitary products on Q&A and organised for the tampons at Parliament, this was half the point.

"We need to liberate the normality of periods," she told Fairfax Media after the dancing protest on Thursday. "And say the word 'period' without awkwardly pausing."

Bringing tampons into the mainstream political debate sends a powerful and important message to girls and young women that what happens to them every month is not something odd or to be embarrassed about – but something that just happens.

Vimalarajah, 21, also wanted to end what she describes as a "ridiculous" tax on tampons and pads, particularly given that condoms get off scot-free. In response to the government's tax review, she started an online petition earlier this month and has since gathered about 100,000 signatures in support.

The law student and social activist reasoned that this was an issue that could not only gather mainstream support but was also small enough (it is estimated tampon GST earn states about $30 million a year) to be achievable.

It is stunning to think that with a bit of smart strategy and a well-timed question to a live TV show, Vimalarajah has been able influence the government's agenda (this week is supposed to be about how bodacious the budget will be for small business), get further on the issue than anyone else has over the last 15 years and get everyone else talking about a taboo subject.

Whether or not you agree with the merits of scrapping the GST on tampons (economists think it is a silly idea), Vimalarajah has proved that individuals really can cut through the bluster and might of Canberra. People power is not just a thing that happened in the sixties. Or a fake concept invented by Twitter.

The tampon tax repeal fight has also proved that politics doesn't always have to be boring or led by the sound bites of middle-aged men in blue, or any other coloured ties.

As Vimalarajah explained: "Just because an issue is serious doesn't mean you can't have a good time raising it."