Crosswalks are ground zero for street photography. One of my favorite street photographers, Tokyo's Tatsuo Suzuki, does a lot of his work walking through Shibuya Crossing where he always has thousands of passing faces to choose from. Having strangers in close proximity with a wide open space around you, which usually means more (or at least more uniform) light than on the sidewalk, is perfect for using a mid to wide-angle lens with zone focusing to get street portraits. There's the added bonus that people are so focused (forgive the pun) on getting to the other side of the street that they're less likely to stop and yell at you for taking their picture.
So I use crosswalks a bit for standard street photography...
But what's drawn me more lately is using crosswalks for abstract bokeh experimentation. They're good spots for that because the various background lights will be nice and far away (and completely out of focus), and no matter how abstract the shot is the white stripes give an easily recognizable reference, and nicely frame the dark silhouette-blobs of anyone in them...
I've written before what a great bargain the Helios 44-2 58mm f/2 is. One of the reasons it's one of the best lenses you can find for under $50 is the bokeh...
Next up is a more obscure lens, at least going by popularity on flickr - the Asahi Takumar 35mm f/2, which I found mounted to a Pentax in a bin of old film cameras. The camera's price tag said $80. I brought it to the register, unscrewed the lens from the Pentax body, and told the store owner, "I don't need the body." He replied, "I don't need the body." I said, "How about $75 for the lens?" and she said sure. Probably not perfect haggling on my part, but it was a good deal for both of us - they go for around $125 to $200 on eBay, but this one is pretty beat up and hazy.
One more, this time back to the Jupiter-3...
...I liked how the abstraction doesn't make it any less clear what's being shown here - I was lucky with how well the white of the crosswalk so nicely frames the couple's interlocked hands. When I posted it on 500px, photographer Joseph DiPolito commented with a more clever caption than I ever would have come up with - "Love is always out of focus."