Parkdale is a portable benchmarking tool which can measure the performance of your local, optical, external and network drives.
The program is unusually configurable, offering you a choice of three drive access methods (Quick, File and Block).
Each of these then has many additional options. Select the Block Access method, for instance, and you get to decide whether the program should use linear or random access; the start and end blocks, as well as block size, whether you'd like to save the raw data, and more.
The results can be displayed as a graph, or in pure figures.
If you need even more control, then the program can alternatively be run from the command line, which makes additional options available. Click the Help link top-right of the program screen for more information.
And once you've finished, you can submit your results and compare them with others.
-New: Block access graph looks better now
Parkdale is a little more complex than it really needs to be, but the program does score for its configurability, so if you're looking for a flexible drive benchmarking tool then it could be worth a try.