London is ready for the opening of the 2012 Olympic Games. Image: London 2012.

The eyes of the world will be on London tonight as the opening ceremony will mark the start of the London 2012 Olympic Games. The ceremony will feature the largest harmonically tuned bell in Europe, NHS dancing, the Queen will be there too of course, and the grand finale will be the entrance of the Olympic torch to light the cauldron.

While London has been gearing up for these momentous events, we here at Plus have been busy too. We've come up with our very own prediction for the medal counts of the top 20 countries. You can see the predictions and how they compare to the actual medal counts on our interactive map, which will be updated daily during the Games. You can see how we came up with the predictions in the article Mapping the medals. And we've got a challenge for you too: why not come up with your own mathematical model for predicting the medal tallies? You can share your predictions with us by posting a comment below. The best predictions will not only gain their authors the fame and glory of being published on Plus, but also a set of our beautiful Plus travel card wallets!

Throughout the Games we'll be bringing you regular blog posts, commenting on what's been going on and pointing you to interesting sporty content on Plus and elsewhere. Meanwhile, check out our sister site Maths and sport: Countdown to the Games, Olympic articles, puzzles and activities on our other sister site NRICH and the collection of maths and sport articles here on Plus. Let the Games begin!