I have to give credit to my brother for showing me this collection, but Facets by Justin Maller is just about one of the coolest things on the web. I can say this wholeheartedly because it's been almost a year and a half since I first copped the link from my brother, and I still go back on the website every now and then to browse the collection. Over the period of a year, artist Justin Maller created a new image everyday - available online for your viewing pleasure.
The cool thing about this collection, specifically, is that all the images are available to download free on his website - meaning you could, realistically speaking, have a different background on your laptop for everyday of the year. He's also got an app for for sale on iTunes called Facets 365, which are versions of his illustrations created especially for the dimensions of an iPhone.
With tons of circulation of inspiring images on sites like Tumblr and Pinterest, it's cool to find actual artists who consistently produce amazing pieces and offer it in high-res for free. Just another reason to love the internet. See some of my favorites below.
Raja, Walther, and Grinner from Facets by Justin Maller