[ctdonath]

I've long observed there's a small but profitable industry in proposing & researching megaprojects: suggest doing something so intriguing and outlandish and expensive that somebody will figure it's worth coughing up a minuscule percentage of the ginormous price tag to fund at least an amusing cursory overview, at a price sufficient to employ a small team for several years. Space elevators, floating (ocean) cities, bridging the Strait Of Gibraltar, world-spanning freeway, FTL interstellar travel, mile-high buildings, etc all are engaging concepts that people with deep pockets are willing to toss some "pocket change" at, giving a group a tidy sum to live on for a while doing something amusing.