For the past year I've been seeing this vibrant cobalt blue color everywhere–from web design to fashion to nail polish to cars. It started on the runways a couple years back and is now a go-to color in web design.
It may be inspired by cobalt blue paint, however I also think it's reminiscent of the classic "Hyperlink Blue" found in links on the internet–hexcolor #0000FF. Since everything from the early 90s seems to be back, it has a "retro internet" quality and is a fresh departure from corporate blue (LinkedIn/Chase) or turquoise blue (Facebook/Twitter) which have become ubiquitous in our culture.
A little history: the blue used for hyperlink was randomly chosen by Tim Berners-Lee, the main inventor of the web. Mosaic, a very early web browser, displayed webpages using black text. The darkest color available that stood out from black, and wasn't was this Blue. And it stuck.
Everything old is new again.