Ingrid Aspock, inspired by the smudges on her iPad, created this set of quirky fingerprint art (They even come in the form of iPhone cases!). Doesn't it remind you of those good old days as a kid, dipping your fingers in jars of paint and smearing it everywhere? Speaking of fingerprints, I remember my grandparents used to hold me in their lap and I'd feel so grown up using my thumb as a stamp to "sign" the bills. Oh the good old days...
Here's more of her work if you're interested.
Good luck with finals, the end is near!