In Business Basic there is a function, DSZ, that shows the current 
amount of memory used by the program code and data.  This was obviously 
more useful in the past where each user might have only 16 KB of memory 
available.  I was wondering if Ruby had something similar while thinking 
about a program.  The brute force method could easily take many GB of 
memory to solve the problem, while a better algorithm might take a few KB.
Something like this may be useful if developing a program to run on both 
a modern PC and something like a cell phone.  One could see if they are 
using too much memory or if it increases as the problem gets bigger.