For those of you hanging out for a local Kindle Fire launch, good news - by the time it gets here, you'll probably be able to run a highly polished version of Android 4.0 on it instead. How do we know this? Because someone has already gotten a relatively stable install to go already.

How many people have you killed in your valiant attempt to end World War III? Among all the countless hours of game play worldwide, billions and billions of virtual people have met their ends during various editions of Call of Duty: Modern Warfare and other first-person shooter games. This might be an affront to international humanitarian laws, according to the International Committee of the Red Cross.

We hear about evidence for water on Mars more regularly these days, but we're pretty sure this is the first time a discovery has been described as "slam-dunk" evidence of a wet past on the Red Planet. The rover Opportunity has found bright veins of what is probably gypsum in the rim of Mars' Endeavour Crater that were almost certainly deposited there by water running through underground fractures in the rock, researchers say, and that points to a past Mars where liquid water was present.

Given a choice between eating chocolate alone and rescuing their pals, rats will apparently save their pals and then share the chocolate with them. Trapping a rat in a cage sparks its cagemate into action, as it figures out how to open the cage and liberate its jailed friend. This is an unusual example of rats expressing empathy, a trait thought to be reserved to us higher mammals, the primates.

Given a choice between eating chocolate alone and rescuing their pals, rats will apparently save their pals and then share the chocolate with them. Trapping a rat in a cage sparks its cagemate into action, as it figures out how to open the cage and liberate its jailed friend. This is an unusual example of rats expressing empathy, a trait thought to be reserved to us higher mammals, the primates.

One of the most controversial science stories in recent memory, the saga of arsenic-loving microbes, resurfaced again this week, a year after the initial claims created a media firestorm. Now scientists at the University of Illinois-Chicago have sequenced the genome of the disputed bug, a step toward comparing its genetic predisposition (or lack thereof) to surviving incorporation of a toxic chemical.

Today in pretty space pics: Using the Spitzer Space Telescope's knack for infrared imagery, astronomers have snapped an image of the most crowded grouping of supermassive stars ever spotted in the Milky Way. Dubbed the "Dragonfish," the cluster of stars, gas, and dust contains hundreds of the largest class of stars, most dozens of times larger than the sun.

Anyone who has ever owned a telescope understands the feeling of anticipation that comes with a cloudless, moonless night. Whether it's humid and mosquito-y or freezing cold, when the stars show themselves, you do what it takes to prepare for a night outside. What should I look for tonight? Maybe a nice globular cluster; maybe Jupiter at opposition, looking graceful through new colour filters.

Sony made a DSLR that could continuously refocus high-speed bursts last year, but that camera's slow-to-refresh LCD viewfinder often displayed a delayed view of subjects. So on the 24.3-megapixel A77, the company swapped the LCD for a 2.3-million-dot OLED that responds to changes millions of times a second - fast enough to keep up with a sprinting quarterback. For continuous focus, a two-way mirror bounces light up to the autofocus sensor at the same time that the previous shot hits the image sensor. $2,799

OnLive has been around for a little while now, but it's no less improbable than it was when it was announced (at which time some gaming blogs called it a technically impossible scam): a service that streams full games, from major publishers, right to your TV or computer, no console necessary. This week, the company will release mobile apps for smartphones and tablets. Let me say that again, in case you don't realise how bonkers this is: You can now play Batman: Arkham Asylum, a demanding and graphically intense game, on your iPad. And it works.

High in a misty valley in the Basque Pyrenees, miles from the ocean and surrounded by verdant sheep pastures, lies a prime surf spot. Its swells break with no wind or reef, and you can turn them on and off whenever you want. While a surf spot might form over hundreds of thousands of years, a team of Spanish engineers took the Wavegarden from concept to reality in just ten.

When a satellite becomes unresponsive in orbit, there's not much to be done - engineers can try in vain to hail the spacecraft and send it instructions, or perhaps blow it up in a show of bravado. But fixing it is pretty much out of the question, especially now that the space shuttle is retired.But what if a remotely operated robot could do the job? Engineers at Johns Hopkins University have been working with a da Vinci surgical robot in a test of long-distance mechanical repair - call it satellite surgery

It's long been something of a holy grail for those bent on the idea of recreating species lost to the Earth through extinction, and now the Russians and Japanese are actually planning to do it - we're going to clone a woolly mammoth, you guys. That's right. Using intact bone marrow recovered from the thigh bone of a woolly mammoth found in the thawing permafrost of Siberia, researchers think they will likely clone a living, breathing mammoth in just five years. (Whether we believe them is a different matter entirely.)

Three decades ago, Volkswagen engineer Peter Hofbauer found himself staring at a Beetle engine's cylinder head - that awkward slab of metal sitting on the combustion chamber-and wondering, Can't we just replace that thing with more pistons? The answer turned out to be yes, so he eventually started a company, EcoMotors, to do just that. The company's product is the opposed-piston, opposed-cylinder engine: OPOC. Each OPOC engine consists of two horizontal cylinders, each containing two opposite-facing pistons. Twice the pistons per cylinder equals almost twice the power. OPOC weighs 30 per cent less than the most efficient turbodiesel engines, and it has the highest thermal efficiency of any automotive engine in the world, converting as much as 50 per cent of the energy in gasoline or diesel fuel into propulsion. A small OPOC-powered car could approach 50 kilometres a litre.