In no particular order:
Intense night-time thunderstorm, August 5th 1997, Jersey, when camping. A man got electrical burns from lightning nearby on the campsite.
Intense night-time thunderstorm in Limoges, France that blew up the power in July 1999.
Thunderstorms in Dubai on 9th March 2016, which caused street flooding, and the Burj Khalifa had lightning come off the top when I went on the outside deck in the storm on the 148th floor. Part of the time I was also inside the storm cloud.
Continuous lightning in a storm in Windsor, Berkshire 3rd July 1999.
Thundery squall line with hail on 31st January 2013 in Buxton, Derbyshire
Thunderstorm that was tornadic when I was in Lincoln on 29th September 2006. Extremely loud thunder.
Beast from east in March 2018 memorable for the big snow drifts and as I was living in an unheated flat in Buxton, Derbyshire, indoor temps got down to 1°C.
July 2007 for the constant rainy days and floods.
December 1990 midlands blizzard that was my first ever weather memory.
Thunderstorm at night in Staffordshire, July 6th 1991 I believe, first thunderstorm memory.