What should be PAT tested? The simple answer to that question is anything connected to the mains supply via a plug and capable of being moved whilst still connected to the supply. This is not the whole story because even items that are not able to be moved, like a built-in dishwasher or heated towel rail also need to be PAT tested.
Cordless power tools do not need testing but their battery chargers do.
IT equipment needs PAT testing.
Power cords to IT equipment also need to be tested, however they need to be tested separately from their equipment, as these need to be tested to a different standard.
Electrical cable extensions particularly needs PAT testing as these are one of the most common sources of hazard.
110 volt equipment as well as 3 phase equipment also need to be tested.