Benfits:
Huge savings in useless job centers, administration and form filling.
Saving in badly targetted working family tax credit and family allowance.
Save hugh amounts of cash as the unemployed choose to take jobs since it's in their interest. No need for miminum wage as people are guarenteed an income anyhow.
All unemployed people would be automatically better off than if on the dole. They might well choose a part time job and get back into work that way.
Move away from the idea that the government should try to make people work as this has clearly failed. If we try even harder then there could be social consequence such as higher crime.
From a Personal Point Of View:
I spent couple of years on the dole and have claimed working family tax credit in the past so I understand how any man hours are being wasted in these departments. I also knew many people who could not take a job without being worse off.