I am planning in making a tabletop, with rounded corners, and want to decorate the top with some grooves that I could make with the router using the edge guide.

Something like this (excuse my drawing skills):

Apart from this model with three rectangular-shaped grooves that I quickly thought out, are there sites/sources of ideas/plans, ready made?

Actually I don't know what keywords to use to search for this kind of technique and designs. Help on technical taxonomy is welcome.

L.E.: Thanks to mmathis, I updated the question title, "inlay" being the design that I am looking for