RAM drive for compiling - is there such a thing?

Question

An answer (see below) to one of the questions right here on Stack Overflow gave me an idea for a great little piece of software that could be in

Answer 1

We used to do this years ago for a 4GL macro-compiler; if you put the macro library and support libraries and your code on a RAM disk, compiling an application (on an 80286) would go from 20 minutes to 30 seconds.