The last week has seen the price of bitcoin gradually slipping back towards the $600 (£350) mark, having been over $650 just seven days ago.

The price dropped a further 2% in the last 24 hours briefly dipping below $620.

In the same period litecoin, darkcoin and dogecoin have all made gains - of 3%, 11.2% and 5.5% respectively - while Peercoin on the other hand saw a dip of 4%.

XXXcoin, which launched last week and caters mostly to viewers of online pornography, repeated the success of earlier in the week by climbing another 80% in value in the last 24 hours.

ISIS claims bitcoin could enable jihad on a large scale

A blog linked to the Islamic State in Iraq and the Levant (Isis - also known simply as the Islamic State) claims the militant group could leverage the anonymity provided by cryptocurrencies to "enable jihad on a large scale" by sending "millions of dollars" to fighters.

The blog - entitled "Bitcoin and the Charity of Violent Physical Struggle" - was sent to Sky News who say the author believes using bitcoin would make donations "untrackable" by Western governments.

While bitcoin does offer some anonymity protection, it is not completely untraceable but the blog references Dark Wallet, the encryption-focused bitcoin wallet which is currently still in development.

According to the post: "This allows our brothers stuck outside of the ardh Dawlatul-Islam to avoid government taxes along with secretly fund the mujahideen with no legal danger upon them.

"This system has the potential to revive the lost sunnah of donating to the mujahideen, it is simple, easy, and we ask Allah to hasten it's usage for us."

Update to core bitcoin version to bring smarter transaction fees

The chief scientist of the Bitcoin Foundation, Gavin Andresen, has announced details about new floating transaction fees which will be included in the code of the next Bitcoin Core release.

In a blog post, Andresen said: "Instead of using hard-coded rules for what fees to pay, the code observes how long transactions are taking to confirm and then uses that data to estimate the right fee to pay so the transaction confirms quickly– or decides that the transaction has a high enough priority to be sent for free but still confirm quickly."

What this means in practical terms is that transactions should confirm more efficiently as the new code will determine transaction priority.

French police bust illegal bitcoin exchange

French police have seized 388 bitcoins (worth £140,000 at today's value) from a bitcoin exchange which was operating illegally in the country.

Three people were arrested in Cannes, Nice and Toulouse on suspicion of operating a website which illegally sold and lent bitcoin to its registered users.

The website was unapproved by the Autorité de Contrôle Prudentiel et de Resolution, the group responsible for supervising the banking and insurance sectors in France.

France regulates bitcoin heavily with the central bank issuing a warning against the volatility of bitcoin at the beginning of the year, claiming that while it does not pose a threat to financial stability, but poses risks for those who choose to invest in it.

Dogecoin racer suits up for Iron Man

Josh Wise, the Nascar driver whose car was sponsored by donations raised by the dogecoin community has revealed that he is taking his support of the meme-based cryptocurrency one step further - by competing in an Iron Man competition wearing a suit emblazoned with the dogecoin logo.

We're not sure if the dogecoin logo will help him in the race, but it looks like Wise is a fully fledged Shibe for life.