Memory mapped files are brilliant when you need to extract tiny bits of data from files that are much much larger than the total memory your system has.
So you don't go banging your head around the next time you try to use a static variable in a class in C++ : http://weblogs.asp.net/whaggard/archive/2004/11/05/252685.aspx
I'm a regular vim user. Recently I came across the c-vim package which adds support to vim for C and C++. Most of you are already aware of this, for those who aren't here's a start.
You can get it here : http://vim.sourceforge.net/scripts/script.php?script_id …