Companies that have been featured on ProductHunt typically will have a welcome interstitial on the top banner for referrals from PH. Is there a way to set this up for any website?
One easy way of doing this is to make sure the URL you submit at Product Hunt has a parameter attached, something like: www.website.com?ref=product-hunt. You then check if this parameter exists when someone lands on the page, and if so you show the banner. You can also check origins, but I find parameters quicker to work with.