Active@ Partition Manager is a lightweight and entirely free tool that will help you take control of your drive's partitions.
Most of its functions are quite basic. You can only create, format and delete partitions, for instance: there are none of the more advanced options, like resizing or moving partitions, that you'll find in more complete commercial tools. And file system support is restricted to the essentials only (FAT16, FAT32, NTFS).
This does make the program easy to use, though, for the most part.
Although, curiously, the program does include an extremely advanced feature in its ability to view, edit and generally manipulate drive boot sectors. A couple of clicks reveals information like the number of sectors per cluster on your drive, its media descriptor, sectors per track, and MFT starting position, amongst a host of other technical details, as well as letting you edit them.
This feature alone makes the program worth installing, if you're a Windows and hard drive expert. Although if you're not, be extremely careful here: make a mistake when tweaking settings and your hard drive may become inaccessible.