The world's largest publishing event, the Frankfurt Book Fair, opens its doors to the public this weekend after hosting industry professionals all week.

Here are five things to look out for at the annual literary feast:

- Hear, hear -

What book are you listening to? If industry experts are to be believed, e-books are out and audio books are in -- with a little help from online streaming services and star narrators. Why read Hillary Clinton's new memoir, "What Happened", when you can listen to her telling her own story on your smartphone?

Publishing giant Penguin Random House said at the Frankfurt trade show that it was seeing double-digit growth in audio books around the world. "It harks back to telling and listening to stories around the campfire," CEO Markus Dohle told reporters. 

- Spruce up your Wikipedia page -

If you're important enough to have your own Wikipedia page but have always been bothered by the unflattering open-source photo used, step into Wikipedia's portrait studio. You'll be in good company: Belgium's Queen Mathilde was among those getting snapped by the online encyclopedia's photographers at the fair.

Or maybe you want to fix a mistake you've spotted in a Wikipedia entry? Take a seat at one of the laptops on hand and set the record straight. 

- Bedtime story -

So many books, so little time. If you really can't drag yourself away, Frankfurt's smallest hotel room may be for you. Located on the top floor of a four-storey container tower with a panoramic view of the fair's courtyard, it comes with a queen-size bed, fluffy white towels and an author at your bedside to read you a good night story. 

But don't get too comfy. The whole thing will be live-streamed and posted on YouTube by Swiss publishers Kein & Aber. And check-out is at 8:30 am. The early bird catches the (book) worm.

- Make a wish -

Write down your deepest wish on a piece of paper, slip it into a slot along with some coins and wait for a personalised drawing to come out some 15 minutes later, created by a group of artists hidden from view inside a "human vending machine". 

But be careful what you wish for. If you're not back in time to pick up your creation, it goes on the wall along with your handwritten note, revealing your most personal thoughts. One such forgotten wish that read "More time to live" was rewarded with a sketch of a chubby horse blissfully skipping through a meadow. You'll have to queue for this one.

- Get political -

From exiled Turkish writers condemning their government to an outcry about the return of a German far-right publisher to the fair, this year's extravaganza is more politically charged than in previous years.

Demonstrators carrying signs that read "Stop Racism" staged a protest at the stall of the small but controversial "new right" publisher Antaios, which in turn complained that some of its books had been smeared with toothpaste.

A few stalls down, the German-based Anne Frank educational centre encouraged visitors to take a picture of their mouths to show that they will speak up against "rightwing populists and extremists".

Elsewhere, British author Ken Follett and Queen guitarist Brian May both railed against Brexit.

"I'm a European and I think Brexit is a terrible idea," May told German media, emphasising that he was not in any way related to British Prime Minister Theresa May.