It depends on what you consider ‘special skills’. With some excercise, paddling should be feasible for most people.
For the English Channel, you can easily find operators and boat charterers offering planning support or equipment rent: http://www.fullthrottleboatcharters.com/kayak-across-english-channel/
Crossing the Øresund may not be much more than 5km (depending on where you cross) and can obviously be done with very simple equipment. Here’s a video of two Swedes crossing on stand up paddleboards: https://vimeo.com/102203607
As of July 2014, bicycles were not allowed on the Øresund Bridge. Check back in 55 years:
It’s currently forbidden to cycle across the Öresund bridge, a part-bridge, part-tunnel connection between Malmö and Copenhagen, which was made famous by the hit television show The Bridge. But if new proposals by Sweden-based construction company Skanska and Swedish consultancy firm Sweco come into effect, the dream for commuting cyclists could become a reality.
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The bike lane, referred to as a “super cycle path” (supercykelväg), would run in separate tunnel above the cars on the Öresund Bridge.
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A report from the two companies explained that growth is expected to skyrocket in the Öresund area, meaning an increase of an estimated one million people by the year 2070.
Credit:stackoverflow.com‘