Hey HN, I just launched
https://PostalAgent.com, a site that lets you easily send highly targeted postcards to specific neighborhoods.
I originally built this site 5 years ago but shut it down when my full time engineering job became too demanding, but recently I did a full rewrite with many new features.
To start you can select an area using a City, State, or even by circling specific areas on a Google Map. Then, you can refine your results and filter on specific demographics, like household income, home value, rental status, etc
You can also search for Businesses rather than consumers, and even filter by franchise type, presence of email, IRS tax code, Franchise Type, etc.
I was able to get a few clients signed up very quickly, mostly home services type businesses and real estate agents, but I think it could be used by many types of businesses. I have a few customers that are only using the mailing list feature without sending postcards, likely for cold email or other marketing outreach.
I'm looking for a bit of feedback from the community.
Also some national postal services sell this "feature".