Atomic clocks are based on two-state systems and the uncertainty in their time measurements is constrained by the uncertainty relation between the phase and the rate at which that phase changes. This implies a quantum limit on how accurately time can be measured using conventionally accessible states. Now Ian Leroux and colleagues at Massachusetts Institute of Technology have found a way to get round this limit. The idea is to construct squeezed states that allow the uncertainty in one variable to be pushed into another, so time can be arbitrarily precisely measured without violating the uncertainty principle. The technique opens up the possibility of better GPS-like navigation and precision experiments than were previously thought possible.