h2g2 The Hitchhiker's Guide to the Galaxy: Earth Edition

For example, I read that a space elevator is feasible using current technology but it would cost trillions.

I also heard (not so sure about this one) that a time machine would be makeable but would also cost trillions.

There's already an ongoing space-elevator competition (rather like the recent flight into space competition - which a company achieved):

http://www.elevator2010.org/site/index.html

A comparison point:- Look at two of the biggest expansion periods in the 20th Century where money really was no object - 1914-19 and 1939-45.

In 1939 we were barely out of biplanes: by 1945 we were in jets.

Look at the way medical technology surged forwards with governments offering research a blank cheque: by 1945 most of the major advances in plastic surgery that we take for granted today had been devised, in order to heal and restore 90% burnt or maimed aircrew, tankers and sailors. In 1939 this was an unknown area of surgery. Penicillin would not have been refined were it not for WW2: and a host of lesser surgical and mediacal advances came out of the necessity of the war years.

So what good is the (bogus) war on Iraq doing ...

More useful lessons in coping with ever-decreasing resources?