Some artists go to the Threadless website for the competition, to craft T-shirt designs that will win a given week's online contest.
Some go for the constructive criticism, the feedback -- good, bad and brutal -- they get from fellow artists about their work.
A few even go for the compensation, the payout that winning designs garner.
But they stay for the community, a coterie of creative sorts, thousands strong, who bond online on a daily basis.
"What makes this a success is getting immersed, all the interactivity," said Minneapolis graphic designer Phil Jones.
Eight of Jones' designs have become Threadless T-shirts, and one of them appeared in the recently published "Threadless" -- a book by Jake Nickell that chronicles, as its subtitle says, "10 Years of T-shirts From the World's Most Inspiring Online Community."
Nickell, who was born in Rochester, Minn., was a 20-year-old art-school dropout when he co-founded the website, then called Dreamless, a decade ago.
"It really started as a hobby," he said, "something fun to do with a lot of artists I know online."