I've always loved watching flowing water, reflections in water, dripping water, waves, waves breaking, looking through ice, ...
A few years ago I did some experimenting flashing light though water streams with coloured paper and card behind and got some cool effects. One of the images was even used by a friend for an album cover that he paid good money for :-) Still lots to experiment with here - not sellers for me on DT but colourful and fun.
I love any type of reflection, especially abstract, over a water body. This is one from the Parliament of Brazil. I have others but need to upload them.
Long exposures of waves crashing in leaves a pleasing appearance - it is always exciting to see what an exposure time will yield - I love the really long exposure streaky shots or those of streams of water exploding on rocks. This is from Vanuatu
Blue water meeting blue sky on a horizon makes for peaceful scenes. This shot was south of Perth around Margaret river.
Fountains are another great use for water and make for great subjects. This is one of my favourite shots at the moment - I love the shallow depth of field and contrast of water vapour to ripples
Churned up water behind a boat was a good subject. Needed a fast exposure time to freeze the texture.
The last one I have is of clouds that I took as the plane rose above a constant cloud layer
A great subject - have lots more experimenting to do.