About 15 years ago when Alitalia was selling off their MD-8 aircraft for $1 million per unit,  I thought of buying them and fitting them with bunks as a round-the-world service for backpackers. For a lump sum, passengers can hop on and off anywhere along a fixed route serviced by daily flights. Stops would be in exotic places rather that major hubs. The route would change monthly as seasonal requires. The planes would fly west to east using the jet streams.

So, the same now, most the Airbus A380s  and Boeing 747s are grounded and some will never fly again. How about using these as flying hotels/hostel? This would work without any change to the plane's furnishings but the ideal concept is an upper first-class deck with larger restaurant/ lounge plus accommodation for personnel. A lower economy deck as is but one person for each three seats to make up a sleeping space at night. Passengers can then be allowed three hand-baggages. No, check-in baggage, the space can be used for cargo or just left empty to save fuel.  Daily free disposable underwear and t-shirts!  A spa/pool/resort is visited every second day. Since the plane purchase cost is already written off, saving fuel because of less weight and less board-personnel would bring the price down to $1000 per day per passenger, upper-deck double price? Would anyone pay that?  Any other estimates of cost? The planes are basically written off, only maintenance, fuel, fees and personnel would be costs?  Even just parked, would make a great airport-hotel?  Design concept: 

More than 200 destinations can accommodate the A380, some A-t-W examples: (image by www.airbus.com)

Another wacky idea by Rangutan 2020 ( original idea 2012)

A380s and B747s as hotels at airports?

A380s and B747s as rest areas for airport staff? 

A380s and B747s as sleeping quarters between shifts at airports?

A380s and B747s as clinics for disaster events?

A380s and B747s as commanding office area for disaster zones?