The crafty folk at XDA Developers have come up with the jailbreak, handily packaged into a batch file that you run each time you turn the tablet on, so you can install apps that haven't been aproved by Microsoft.
The jailbreak exploit works on Windows RT, the tablet version of Windows 8 found in the Surface and set for a range of tablets from (a small number of) other manufacturers. RT is designed for the low-powered ARM chips found in tablets. It's a stripped-down version of the software that only runs apps from the Windows Store, unlike the full version of the software that allows you to install any app you fancy.
Applying the jailbreak allows the tablet to run apps that didn't come from the Windows Store, although applications designed for a computer's x86 processor won't work on the tablet unless recompiled for the ARM architecture.
The full version of Windows 8 is set to appear on a tablet in the shape of the Microsoft Surface Pro, which is expected in the US this month but is yet to have a British release date confirmed. Meanwhile the different versions of Windows 8 have caused enough confusion to see theSamsung Ativ Tab cancelled.