A code sprint is a gathering of a bunch of programmers to complete a short, rapid development project. A sprint usually uses ExtremeProgramming methods, such as a PairProgramming and TheCoach keeping the tempo of about an iteration per hour. It allows developers from different companies to work together and learn from each other. Most importantly, it's a fun weekend where we can make some impressive advances in interesting projects.
PythonSprints, such as the XpCodeSprint in Portland 2005, are the most common.
A good guide to sprinting: