Giving people what they do not need: mild panic
A little while back, I tweeted out an emoji that I made that I lovingly called “Mild Panic” and it went pretty dang viral all over Twitter and Reddit.
After the notifications died down, I thought, “hey, let’s put this emoji on things” and threw up a Redbubble page. It cost me a total of a dollar (plus some time to actually make a higher res version of the emoji) to do so, and I’ve made like… $4 total putting it on products:

It’s silly, it’s dumb, and nobody wants this, but hey, I’m a giver. ;)
A few friends of mine use these sites (plus Threadless and I’m sure there’s others) for side income, and I thought it’d be fun to check it out and see how it works! I don’t know if I’d do it more because it’s definitely more work than it seems to be worth, but it was fun laughing at this face plopped on a variety of products!