The main program tests database type access to a single file (or a set of files if you wish to test more than 1G of storage), and it tests creation, reading, and deleting of small files which can simulate the usage of programs such as Squid, INN, or Maildir format email.
The ZCAV program which I initially released as a seperate package tests the performance of different zones of a hard drive. It does not write any data (so you can use it on full file systems). It can show why comparing the speed of Windows at the start of a hard drive to Linux at the end of the hard drive (typical dual-boot scenario) isn't a valid comparison.