TeeSpring - Create & sell t-shirts you can be proud of
Product Hunt - A website that lets users share and discover new products
Merch by Amazon - Create, sell, and promote custom branded t-shirts
Printful - White-label printing under your brand. Free shipping and 20% off samples + 3 day average turnaround.
Swag for Dev - A list of opportunities for developers to score some swag 😎
RedBubble - UNCOMMON DESIGNS BY INDEPENDENT ARTISTS EVERYWHERE