easyJet state:
Save where the limits set locally are more restrictive, passengers are permitted one standard piece of hand baggage to a volume limit of 56x45x25cm (including wheels and pockets) (“Standard Hand Baggage”). It must fit without force into the gauges provided at check-in or departure gates. No weight restriction applies within reasonable limits — i.e. a passenger must be able to place the piece of luggage safely in the overhead storage bins without assistance.
In addition to the “Standard Hand Baggage” you may also carry:
(a) one of the following: An overcoat; an umbrella, or a shawl; and
(b) one standard size carrier bag of goods purchased from the departure airport.
To my mind, that is madness. Ryanair's policy is considerably safer!