Most upvoted comment
A backpack that charges your smartphone and tablet!(r/shutupandtakemymoney)
Holy shit! $99 for a backpack with only a 3000mAH battery? Buy $20 backpack and pickup this:
$76, with 4 times the capacity. 5 stars as well with 728 reviews
Note the amazon link is clean and contains no affiliate link. Just a satisfied user.
EDIT: Reddit Gold?! Sir or madam, I am humbled! Thank you!