I was about to give up until there was a dominoes sale at Target. Who needs tiles? Dominoes are much more fun!
Step 1: Materials and Testing Layout
NOTE: One thing you might want to consider is that once you have your layout, you might want to construct a frame around the edges of the table. (We couldn't do this "easily" because we had a slight overhang to all sides.) In the end, we were a little off in one direction and the spaces between dominoes increased on that direction as we reached the center. The frame, perhaps nailed in place, will insure that your layout is tight-fitting.
+tube of construction adhesive (we used about half a tube): $3
+about 250 dominoes: $20
+time: 2-3 hrs
Step 2: Begin placement
Step 3: Finished!
Note: Unlike with smooth-faced tile, you can't simply spread grout to fill gaps and wipe away. Whatever is used to fill gaps can end up in the domino holes. You'll need wet Q-tips for clean-up.
You might also want to paint the table surface white. Where the adhesive doesn't fill gaps, the dominoes have rounded edges, so you'll be able to see between even the tightest fitting pieces.
If you go with a overhang, you might make it large enough to edge the table with more dominoes.