Have you heard of bokeh before? Technically, bokeh is the "aesthetic quality of the blur produced in the out-of-focus parts of an image produced by a lens." But to my eyes, it's pretty much just a bunch of dazzling shapes, shades and lights! I've never been good at intentionally creating this effect, but I never fail to be impressed by those who can use bokeh to their advantage, like this awesome photographer.
Takashi Kitajima is a Japanese computer engineer who works all day but manages to take absolutely beautiful photographs (heavy on the bokeh) at night.
Here's a few of my favorites of his! You can find more on his flickr.