FloodMap shows maps depicting the outcome of raised (or lowered) sea levels on the world's coastlines. It uses OpenStreetMap data, has a box to enter how many meters of water you'd like added or removed, and has topical forecasts of flooding and a newfangled 3D visualizer. It doesn't do anything fancy like simulate erosion or isostatic rebound.
Above is the U.S. with all the ice melted, yielding about 70-75 meters of sea level rise. This marks a theoretical limit, barring unlikely cosmic encounters with interstellar hydrogen clouds or what-have-you. Even the most catastrophic long-term projections land at less than half that, which is still not enough to completely inundate Florida.
See also the NOAA Office for Coastal Management's Sea Level Rise Viewer, more detailed but limited to credible intermediate-future outcomes (+/-10ft of high tide).
Previously:
• Ominous sea level report card for most U.S. coastal communities
• Fashion designers prepared for rising sea levels
• Here are 36 cities that will be the first to be submerged as global water levels continue to rise
• Survey finds big cities slowly sinking into ground
