A portable electronic device comprises a base and a cover rotatably mounted to the base. A lever arrangement comprising a co-operating lever arm and a support is defined by the base and the cover. The cover is movable between a closed position and an open position through an over center position by movement of the lever against the support upon rotation of the cover. The cover may be biased toward the closed position when the cover is on a closed side of the over center position and toward the open position when the cover is on an open side of the over center position.