My main web site is "G" rated. When my kids were younger, I came up with the idea of making selling some kind of tacky buttons and name badges. Products that might have some profanity or be a bit bawdy.
But I didn't want to put those things on my "G" rated main web site.
So I got "tackyButtons.com" and "tastelessButtons.com" and never got around to selling profane or bawdy products.