I think that's one of the best types of photography you can do!
Like this picture, 340 seconds of doing nothing, just peace and quiet :p
I love it in the morning, its like therapy, the silence and the birds are relaxing and calming. Its just like meditation.
Took this picture with the Leefilter big stopper and the 0.6 ND graduated filter.
Settings are diafragma F10 ISO 100 and the 340 seconds!
This lake is in the Netherlands, it use to be part of the North-sea but we Dutch don't like the sea because of the risks of flooding! Biggest part of the Netherlands is below sea level. So we build a dike and than there was a lake :p