Here's a little tidbit from my new book (Modern C++ design, forward) that made me laugh out loud. Not a "ha ha" funny laugh, but more so a "You're not supposed to use templates like that! This author must be insane!" laugh. Template<bool> struct CTAssert; Template<> struct CTAssert<true>{}; // ex. usage foo() { // COMPILE time assertion! CTAssert<sizeof(int) == 4> foo; }