Perhaps you've heard that size matters, women are naturally more bisexual than men, or that tantric sex means everlasting orgasms. None of these things is entirely true. Sex has been around forever, but we're just starting to understand it. Today we're debunking 10 of the most common sex myths to set the record straight.

Sleep is a mysterious process, and that means it's the subject of many untruths and much ill-informed wishful thinking. If you're trying to improve your quality or quantity of sleep, don't fall for these myths and you'll be well on the way.

Brain games will make you smarter! The internet is making you dumber! Alcohol is killing your brain cells! The brain is a mystery we've been trying to solve for ages, and the desire to unlock its secrets has led to vast amounts of misinformation. Many of these false notions are more widely believed than the truth. We took our healthy scepticism and a bunch of brain research to find the truth behind some of the most common myths about intelligence and our brains. Here's what we learned.

We love busting myths here at Lifehacker, and because of that, we love the show MythBusters. If you do too, the web site MythResults summarises all 271 episodes of the show so you can quickly see what's fact and what's fiction.

The end goal of productivity tips is to spend less time doing the things you have to do so you gain more time for the things you want to do. But if you follow every morsel of productivity advice you encounter, you'll end spend more time moving papers and emails around than actually getting anything done. Need to simplify your routine? Let's put an end to some common productivity myths once and for all.

Adam Savage is one of the co-hosts of the award winning, and soon to end, show Mythbusters. Obviously safety is a big deal with the entire crew on the show so we asked him what experiment did they contemplate but back out of because it was too dangerous.

Organising tools is tough and if you're someone like Adam Savage, who has hundreds of tools, then you need a system in place. He tries to keep everything out in the open, so he built a couple of his own stands.

Brief news items of note for Lifehacker readers, including: The tech behind FIFA's World Cup goal detection system, Miyamoto tries out virtual reality, Aussie interview with Mythbusters' Jamie Hyneman.

People believe dumb stuff. One dumb thing they believe? That Bitstrips -- those mildly-irritating cartoons being shared a lot on Facebook right now -- are actually a secret spying tool for the US National Security Agency (NSA).

Dear Lifehacker, Over the years I have heard various whack-job anti-government conspiracy theorists and their ilk talk about income tax being illegal. They mention things like "Income has never been defined under Australian tax law", which apparently means we can claim we earned only chickens, conches, ceremonial wreaths or whatever, and apparently this befuddles the taxman into not being able to actually charge us anything. Is there any truth in this, or can it be easily debunked? Cheers, Tax Time Truth

Preparing for your tax return can often seem like a tedious chore, but if you fall for these common misconceptions the task can be even harder. Let's bust some common tax myths.

Brief news items of note for Lifehacker readers, including: Australian Data Retention plan swept under the rug, Steve Jobs movie gets Ashton-packed trailer, Mythbusters celebrates 10th anniversary with episode #200.

Recently released government figures show levels of childhood vaccination have fallen to dangerously low levels in some areas of Australia, resulting in some corners of the media claiming re-ignition of "the vaccine debate". (You can check how your postcode rates here.) Well, scientifically, there's no debate. In combination with clean water and sanitation, vaccines are one of the most effective public health measures ever introduced, saving millions of lives every year.

Ever scoff at someone for buying refurbished? Or found yourself spending $50 on an HDMI cable? We all hear (and spread) tech myths, but in some cases those myths end up costing you a lot of money. It's time to debunk the myths that drain your hard-earned cash from your wallet.

It's widely believed that men have higher body temperatures than women. The observable truth is rather more complicated: there's not a noticeable difference in core temperatures for males and females, so the difference we observe is due to different skin temperatures and varying sleep patterns.

Not everything needs to be complicated! At this year's TED, Adam Savage, best known as part of the two-man team the fronts TV's MythBusters, reinforced this adage by highlighting examples of historic scientific discoveries that were made using straightforward concepts and approaches.

The news that McDonald's will be stopping the use of 'pink slime' -- essentially random beef offcuts mixed with ammonium hydroxide -- in its burgers has been the subject of fervent online coverage. But local Maccas fiends shouldn't panic: the additive isn't (and hasn't ever been) used in the Australian product.

The idea that an adult needs to drink eight glasses of water a day is one of the more persistent health concepts you'll encounter. However, as we've pointed out before, it's almost entirely bogus.