Disk based hashes is a method to create multidimensional binary trees on disk.
This library permits the extension of database concept to a plethora of
electronic data, such as graphic information. With the multidimensional binary
tree it is possible to mathematically prove that access time to any
particular record is minimized (using the concept of critical points from
calculus), which provides the means to construct optimized databases for
particular applications.

Homepage:
http://dbh.sourceforge.net/
