Geocaching is a kind of game related to orienteering in which people hide and seek GPS/GSM receivers at random places of the globe. Some Czech organizations have brought the game to a brand new level: see Stratocaching.CZ and an explanatory article in English or a fresher one translated from Czech.
The video at Stratocaching.cz has 3 tabs, showing the situation in the balloon; control center; and the launch site. The server may be overloaded because billions of people may be afraid of thermonuclear detonations.
A 2-meter-diameter Japanese balloon will be shot to the stratosphere, 30 kilometers above the surface, in a few minutes (9:30 am Prague Winter Time on Saturday). The balloon will grow to 15 meters in diameter before it pops. It contains 10 thermonuclear warheads and 2 ordinary nuclear warheads.
They will explode and destroy the industial civilization in Europe due to some electromagnetic waves, thus returning the old continent by 7 centuries. But this technical detail is not the main part of the game. Each of the thermonuclear warheads contains an indestructible "stratocache".
Inhabitants of the continent which was returned to the Middle Ages will look for these 10 "stratocaches", using their smartphone-like devices with iOS and Android, assuming that they still work. The first 10 people who will find each stratocache will be given some prizes like tablets – 100 prizes in total – which may increase their chance to survive on this inhospitable continent again.
Before Europe is destroyed, you may download iOS and Android applications; search for Stratocaching on Play Store or App Store. Unfortunately, the registration was stopped before I learned about the game at 8:30 am.
The balloon went to 31 kilometers as it was flying from Prague towards Southwest, to my hometown of Pilsen, practically copying the (100-km-long) Prague-Pilsen railway for quite some time. The chance was high that the seeds would land close to us.
The Dropion landed about 30 km from Pilsen. The first seed landed in Chrást by Pilsen, just 4 km from my home (only about 1/3,000 of the Czech territory is this close to me – the number is also the "probability" of something), but it was found by 10 contestants almost immediately. I would probably have no chance to find it in time. The remaining 9 seeds apparently lost their GPS capabilities. ;-) But at 14:05, it turned out that other seeds began to contact "Houston", too.
Another update: almost all the other caches also landed very close to my home, East of Pilsen – Smědčice where I would be going for fresh water; Bušovice where we went to a nice countryside restaurant to have a monstrous St Martin goose lunch exactly 1 year ago, and so on.