Hmmmmm... Question. How to create really really long exposures? How? I mean cheaply, not with some super special addition to gear. What is a ND filter? Or is that more easily done with a trick? Placing multiple ones atop one another? Or what?

A cute list on this blog: http://tamara-linse.blogspot.com/2012/04/100-things-about-photography-by-nithin.html

 This dude left the exposure opened for YEARS.