Some io commands, such as cit::fprintf, cit::sprintf, cit::print using C++11 variadic templates.
This gives typesafe printf-like methods that also enables reusing arguments multiple times.
Example:

const std::string s = cit::sprintf("First element: {0}, Second element: {1}, First element again: {0}", 42, 3.14159);

Also, implode-methods to generate delimited strings from containers and iterators as well as a join-method to do the same with variadic template arguments.