Sugru - Lets you look at the most recent issue of their newsletter before actually signing up for it.
Gidsy - The email newsletter sender address says “email@example.com” instead of the usual “firstname.lastname@example.org”.
/via Koen Claes
Disclaimer: Gidsy is our startup.
West Elm - Gives you the option to just dial down email frequency when unsubscribing from their newsletter.