As was pointed out to me on Haiku's IRC channel, GNU Parted 1.70 now supports BeOS, thanks to the work of Ithamar Adema. Previously only BSD, Linux and GNU Hurd systems were supported, meaning BeOS is the first non-UNIX-alike to run Parted.

Parted allows you to non-destructively resize ext2/3, FAT16/32 and HFS partitions, as well as create many formats. It powers the partition managers of most modern Linux distro installers. While not nessacerily as featured or reliable as the partitioner available on ZETA, albet only in its installer, it provides features that DriveSetup could only dream of, albeit at a command line interface. Unfortunately, theres no BFS support, but there are currently no tools that resize BFS available at all.

The changelog for this release can be found here, and source is available from your local GNU FTP mirror.