This reminds me of a demo a friend once gave me on a Symbolics Lisp Machine. He turned the garbage collector off, then ran a program that allocated memory like

This reminds me of a demo a friend once gave me on a Symbolics Lisp Machine. He turned the garbage collector off, then ran a program that allocated memory like mad. After a while, a message popped up saying something like "you are about to run out of memory. Activate GC?" He declined, and the program continued running. After a bit more time, another message popped up saying "you are about to run out of memory, and if you don't start GC now, there will not be enough room to run it when you do. Activate GC?" Again, he declined. After more time, another message popped up saying "you have run out of memory, and it is not possible to start GC now. Would you like to attach an external disk drive?" The idea was that the external drive could serve as additional memory either to continue running without GC or as scratch memory for the GC. I've always found that impressive.