Linux File Systems for Windows, Ceph, GlusterFS, DiskInternals Linux Reader, XtreemFS, WekaFS, Ext2 Installable File System, DRBD, Lustre, StorPool, macFUSE, Seaweed FS, MooseFS, LizardFS, Quobyte, FSproxy, Fuse4X, Explore2fs, Ext2/3/4 Filesystem Utilities are some alternatives to BeeGFS.