I have taken up the design west hydration coaster, I am planning on using a balance or scale to measure the weight of the drink and measure how much has been drunk. the coaster will then alert you to the fact that you have not drunk enough and how much more you need to drink. this can be used in hospitals, the home and the work place. The coaster should be small to fit on a desk or side table and portable to you can carry it between work and home. the average male should be drinking 3.7 litres of water per day and women should be drinking 2.7 litres per day. the coaster could have a button to change between the two or sell different ones to men and women.