geoConvert-E98.f for GEOS 64 & 128 by Markus Kanet, released on 4/25/1999.  This utility can convert files from GEOS to CBM, CBM to GEOS, SEQ to UUE and UUE to SEQ.  It also supports 80-column mode on the Commodore 128 but I don't have one to test so all the screenshots are from a C64.