CiderPress - Windows utility for managing ShrinkIt archives and Apple II disk images. - http://www.faddensoft.com/ciderpress/
AppleCommander - An open source disk image utility written in Java. - http://applecommander.sourceforge.net/
Apple DOS File System - Shareware utility in development for classic Mac OS and Mac OS X to mount and manipulate Apple II ProDOS, DOS 3.3, Pascal and CP/M disk images. - http://www.lazilong.com/apple_II/adfs/