Alternative Island 3

This is a kind of recurring idea. Another variation is to use
concentraing mirrors to squeeze all the light through a small window
giving acess to the inside of the habitat. The disadvantage of this
maybe just loosing the astronomical view that you would have in a
O'Neil cylinder, but since this disadvantage is purely aesthetic I
think that most people would gladly dismiss it in exchange of, say,
cheaper land inside the cylinder. There may be also engineering
chalenges (the small window may have to withstand high temperatures,
etc), but I think that it is possible to circumvent them.