Partitioning does not waste any space, except when oversized clusters are used. The larger the clusters, the more space is wasted with each file. Your see, if you have a 64K cluster size, then no piece of data can take up less than 64K. So, a 100K file will take up two whole 64K clusters instead of 100K. NTFS is better about this with larger partitions that FAT32. Splitting up your harddisk into smaller partitions will increase the efficiency, but you probably won't notice it too much.