E00Compr is an Open Source ANSI-C library to compress and uncompress
Arc/Info Export (E00) files. It can be easily plugged into existing E00
translators to add support for compressed E00 files simply by replacing
the existing translator's read/write function by the E00ReadNextLine()
and E00WriteNextLine() functions provided by the library.

WWW: http://avce00.maptools.org/e00compr/