Why didn't I think of that?

Yvonne Bekker rolls out her new idea

Now's your chance to tell the world about your ingenious idea for a non-stick rolling pin. That's exactly what Yvonne Bekker from South Africa is doing at the International Exhibition of Inventions, New Techniques and Products in Geneva, Switzerland.

Some 686 inventors from 44 countries are presenting inventions they hope will be the biggest thing since post-it notes. Failing that, they can at least hope to win the prize for best invention.

The exhibition mixes serious business inventions in areas such as architecture, furniture, engineering and computer science with a stunning number of household gadgets. The show is expected to attract about 65,000 visitors.

The event is also about marketing opportunities. Last year, licences were negotiated worldwide for more than £22m (US$35m) during the event.

BBC News online explores some of the wackier inventions.

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One of the most popular items has been created by Irishman Tony Allen, who was tired of climbing over furniture to remove spiders from his arachnophobic son's bedroom.

Allen got to work in his tool shed and came up with a mechanical brush on a long handle, which captures spiders between the bristles without hurting them.

His invention has been so successful that he is now marketing it fulltime. For £12 (US$19), purchasers also get a plastic practice spider.

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Franck Dutrain from France shows his dice with 24 equal faces. It gives more possible outcomes for boardgame players and gamblers everywhere.

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For those worried about what lurks between their bristles, Korean Shin Choong-Sik holds a denture and a toothbrush to demonstrate his invention: the Esencia Toothbrush Sterilizer.

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Toothbrushes provide ample inspiration for inventors. Here, a non-slip toothbrush glass with slots holds a brush in place while toothpaste is added.

"I think it's interesting for those who have only one arm," says its German inventor Helmut Buchmann.

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From the evergreen forests of Norway comes a novel device that is already a test run hit, even though it only gets used once a year. The "Super Grip" is a spring-loaded Christmas tree stand.

"We took 2,000 of them to a small town in Norway and we were sold out in a week. And over 100 million Christmas trees are sold in Europe every year!" says the inventor Alf Aarthun, who is looking forward to the season of good cheer.

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Rowing enthusiasts need never worry about finding a river again.

Now they can take to the road with Aviroute, a training machine for use on the street, as demonstrated by Thierry Suptil from France.

Will rowing to work become all the rage? Watch this space.