Post it in the shower competition: what would encourage people to take a shorter shower?

A thermal spray-on dry gel - similar to shaving gels - that have a sauna effect similar to deep heat gels. Spray on and leave for two minutes before then washing off for two minutes Photograph: guardian.co.uk Photograph: guardian.co.uk

A shower mat that reveals a "keep it short" message after three minutes of being wet. Photograph: guardian.co.uk Photograph: guardian.co.uk

A four minute shower timer called Shower Bob! Photograph: guardian.co.uk Photograph: guardian.co.uk

Special frosted glass on the shower door that starts to unfrost after three minutes of contact with steam. When completely clear, you know it's time to get out! Photograph: guardian.co.uk Photograph: guardian.co.uk

The spider concept: there is a measuring device under the plug hole tracking the amount of water used. Once water use reaches a certain level, spiders are realised into the shower cubicle scaring you out of the shower! Photograph: guardian.co.uk Photograph: guardian.co.uk

A push button shower, similar to those you have in some gyms, that come on for a specific period of time. During a normal shower you may push it five or six times and when the shower stops running, you lather up without wasting water. Photograph: guardian.co.uk Photograph: guardian.co.uk

A four minute shower song that works as an indicator as to when your shower time is up. Wet... lather...rinse...out! Doo-dee-doo! Photograph: guardian.co.uk Photograph: guardian.co.uk

A shower that changes colour relative to either temperature or time. There could be a dye in the water, lights from the shower head or a traffic light system? Great for kids! Photograph: guardian.co.uk Photograph: guardian.co.uk

Shower like a car wash. 1. Take zero bottles in to the shower. 2. System delivers lather through the shower head for ninety seconds. 3. System then delivers water to rinse off lather. Photograph: guardian.co.uk Photograph: guardian.co.uk

Include an egg timer in shower gel bottle to guide usage time. Photograph: guardian.co.uk Photograph: guardian.co.uk

Remote Island Shower: 1. Take an empty plastic bottle 2. Drill holes into the cap 3. Fill with water 4. Close the perforated cap 5. Be suprised by the comfort Photograph: guardian.co.uk Photograph: guardian.co.uk