As a Danish architect unveils plans for a snowflake-shaped floating hotel, Dezeen selects 13 of the most ridiculous, outrageous and unusual hotel designs we've ever published – including a flying whale, a person-sized bird's nest and a room that allows guests to sleep with the fishes (+ slideshow).

Krystall Hotel by Waterstudio

A studio specialising in floating structures – led by Dutch architect Koen Olthuis – unveiled its design for the snowflake-shaped floating Krystall Hotel for an undisclosed site off the coast of Norway earlier this month.

The 86-room hotel will be accessible only by boat and will feature a glass roof so that guests can get the best views of the Northern Lights. It is due for completion in 2016. Find out more »

Innhotel hotel by WAM Architecten

Another Dutch design, this pile of houses is actually a single hotel building designed by Delft studio WAM Architecten for the town of Zaandam, in the Netherlands. The 11-storey building houses 160 rooms and its green shapes were inspired by iconic houses in the Zaan region.

The architects said the project was "without a shadow of a doubt already the main eye-stopper in the revamped town centre and a building that has set many tongues wagging."  Find out more »

Manned Cloud by Jean-Marie Massaud

This whale-shaped flying hotel is a proposal developed by French designer Jean-Marie Massaud with French national aerospace research body ONERA to accommodate 40 guests, plus a restaurant, library, fitness suite and spa.

The airship would have a cruising speed of 130 kilometres per hour and a top speed of 170, and include a sun deck on top of its double helium-filled envelopes. Find out more »

Antony Gormley's ROOM at the Beaumont Hotel 

British sculptor Antony Gormley created this giant sculpture of a crouching man, which contains a £2,500 per night suite, on the side of a hotel in London's Mayfair district.

The space inside measures just four square metres, with a 10-metre-high ceiling and a small window positioned between the legs of the sculpture. Find out more »

Unbalanced Hotel by OOIIO Architecture

Designed for a site on a cliff near Lima in Peru, the proposal for the 125-room Unbalanced Hotel looks like it's crashing into the landscape.

"A hotel with these characteristics and dimensions constructed in a traditional way would be a visual barrier," said the architects from Madrid firm OOIIO. "But, thanks to [the hotel's] peculiar shape, the landscape is now even more relevant - we have framed it!" Find out more »

The Bird's Nest by Inrednin Gsgruppen

This tangle of twigs is just one of a series of highly unusual suspended hotel rooms at the Tree Hotel in Sweden.

The Bird's Nest is supported by existing trees on the site and includes a retractable staircase, with enough space for a family of four inside. Find out more »

Water Discus underwater hotel by Deep Ocean Technology

This hotel looks very much like a concept for a Bond villain's lair, but this one is a real proposal by Polish company Deep Ocean Technology for the world's largest underwater hotel. Inevitably, it's being built in Dubai.

The Water Discus will include 21 rooms, a diving centre and a bar below water level, with smaller disc-shaped structures supported above the sea level on columns to provide additional facilities and that all-important helicopter landing pad. Find out more »

QR-Code Hotel Room by Antoine Peters

The new Hotel Modez in Arnhem has a room covered entirely in scannable QR codes – linking to text, movies and even pornography – with the black-and-white symbols covering bespoke wallpaper, curtain and bed linen.

"The room seems as abstract as it can be, but secretly you are surrounded by porn," said Antoine Peters. "The abstraction of the room symbolizes the fact piquancies are always extracted from the eye, but I think these just belong to hotel rooms. And anyway, aren't we surrounded by porn everywhere nowadays?" Find out more »

The Songjiang Hotel by Atkins

At first glance, the visualisations for the Songjiang Hotel by Atkins don't look all that unusual. But once you work out the scale – the hotel will be built into the 100-metre-high rock face of a disused quarry outside Shanghai – its true craziness begins to reveal itself.

A huge waterfall will pour down from the top of the 19-storey complex, which will be partly built into a cave and have two floors underwater. Find out more »

Alpine Capsule by Ross Lovegrove

If you like remote locations, this is the hotel room for you. The self-sufficient mountain living unit by London designer Ross Lovegrove will be located in Piz la Ila (Alta Badia, Italy) at 2,100 meters of altitude.

The eight-metre-diameter design looks like a metal pebble, but is actually made from acrylic with a reflective coating to create a 360-degree view. Find out more »

Tree Hotel by Tham + Videgard Hansson Arkitekter

Here's another room from the Tree Hotel in Harads, Sweden – a 4x4x4 metre mirrored cube by Tham & Videgård Arkitekter.

The plywood-lined structure is suspended around a single tree trunk and accessed by rope bridge. It's designed to accommodate two people, with a double bed, bathroom, living room and roof terrace. Find out more »

Hiding in Triangles by Philip Modest Schambelan and Anton Fromm

Technische Universität Dresden students Philip Modest Schambelan and Anton Fromm have designed this hotel for mountain bikers for the edge of a cliff in Pregasina, Italy.

Continuous ramps from top to bottom would make the entire structure accessible to bikes, with hotel rooms suspended by cantilevered walkways 500 metres above the northern tip of Lake Garda. Find out more »

The Underwater Room at Manta Resort by Genberg Underwater Hotels

If you've always wanted to sleep with the fishes, but the idea of a huge hotel in Dubai doesn't appeal, it's possible your ideal hotel room already exists 250 metres off the coast of Pemba Island on the coast of Zanzibar.

Part of the Manta Resort, the three-storey floating structure is accessed by boat and includes a bedroom with windows on every wall to create a 360-degree view of the underwater coral reef and sea life. It was designed and built by Swedish company Genberg Underwater Hotels. Find out more »