I've never squeezed limes on tomatoes but it is one tasty combination.
At a farmer's market this morning one vendor had a plate of samples and I thought "this is the best tomato I have ever eaten". Then someone next to me asked if there was anything on the tomatoes besides salt and the vendor said limes were squeezed on the tomatoes.
While I find this a bit deceptive, I liked the new combo. I know in Mexico the squeeze limes on fresh fruit. Never had it on tomatoes though.