If you were thinking of working on a disk scheduler for DragonFly, this is your lucky day!  Brills Peng asked for some overall guidance on how to start on a Summer of Code project.  I threw out some general tips, Alex Hornung talked up resources on kernel programming, and Venkatesh Srinivas described exactly what you’d need to write a disk scheduler.  There’s about 50% of a whole proposal, prewritten.