I really like those resin coffee tables with the blue water effect, they’re very striking. Thought it would be cool to make a world map version, but given how complicated it would be to make such a thing, I started thinking about a simple way to execute the idea: blue glass.
I’m surprised no one has done this yet, at least from what I could find online. So I thought I’d post a concept or two here.
Basically a pane of blue-tinted glass with a map affixed to it (can be vinyl stickers or printed on a clear film), with another pane of clear glass on top to protect it all.
It does look good if you have a light-colored floor (top image), but another way to go is make an enclosed coffee table with a white backdrop beneath the blue glass:
Went with RISK here but any map with a lot of water will look good. Westeros, Azeroth, Elder Scrolls, Los Santos, Last Airbender, and so on. RISK would make for a nice gaming table as well.
This would be a lot easier to execute than the resin approach. Plus these glass tables would be a lot lighter in weight compared to a resin coffee table.
If you want to be extra-fancy you could illuminate this with a light box underneath.
Dave's Geeky Ideas 
The last few seasons of Supernatural have had an abandoned underground bunker with a lit-up map table in the center of what the characters have been using as a living room. It serves absolutely no purpose (it had blinking lights when something bad happened, once), but it looks good and always brightens up the inevitable exposition scenes held over it.