Yup, these are all niche technologies - some of them (airships) had their time, but today they are all much less common than the alternatives ("regular" airplan

Yup, these are all niche technologies - some of them (airships) had their time, but today they are all much less common than the alternatives ("regular" airplanes, regular trains, regular ships). Interestingly there is also a parallel between hovercraft and supersonic passenger airplanes: their best-known applications (Concorde and the hoverferry across the English channel) both started in the 1960s, were never really profitable and were discontinued once the original vehicles were getting obsolete in the early 2000s.