I admit, this prompt is fun. Although it sounds too easy but this had me thinking for quite a while. There are lots of museum established already and I wanted a unique and useful one. It is too hard to choose considering that almost all things have its museum. Granted with five million dollars, I think I'd open a Tourist Spots Museum. This museum will highlight and recreate all known and unknown spots and tourist destinations around the world. This way, people who wish to visit their dream spots but have no means to, can get a chance to see and feel their dreams closer to reality.

         This museum might be too ambitious and impossible to achieve. But there are lots of ways to recreate and make an exact copy of the world's wonders inside each colossal room of this museum. With our technology now, it can be 3D printed. If you love waterfalls, then there would be rooms for that. Caves? There would also be rooms for that. Mountains? Beaches with white sand? They're available. But what all these can give? Can I surf on that copy of your Boracay Beach? These you may ask. No, but you can take pictures while you wear your favorite pair of bikini. Of course, some spots in the room could be interactive and offers the same feel like those of real ones.

         Wow! Having all said that, I don't think five million dollars would suffice to bring this museum to reality. But we can always do a feasibility study for this. Thank you for reading. Cheers!