Check out how cool these silhouette rings are from Cameo by Rux:
They are completely custom so you send them a picture of a profile you want and they create the ring from that.
I think this would be an awesome choice for wedding rings or as a push present for new moms.
At first glance they just seem like ridged rings, but looking at the sides shows you the profile of someone you love.
They come in 18k yellow, white, or rose gold and you can get the skinnier kind or the thicker kind. Thicker ones cost more.
The site also has plastic bangles that feature the same custom profile look, and busts and tops, but I think the rings are the nicest.