I have a 1TB secondary drive on Windows 7 for Backup, WAV (rips from CDs), mp3s, and Podcasts, and I put them on separate partitions to avoid having to worry about fragmentation or having a corruption on the drive screw up everything (I'm assuming a corruption on one partition will only screw up that partition).
Am I unjustified in doing this, or is it causing unnecessary work for the drive, or anything other problems you can think of? I'd fully prefer to have all of this on separate NAS drives but I can't right now.