Ext2Fsd parece com o que você está procurando.
Ext2Fsd is a file system driver that allows accessing (both reading and writing) EXT2, EXT3 or EXT4 partitions from Windows. It works with Windows 2000, XP, Vista and Windows 7.
Ext2Fsd has limited EXT4 support and by default it will load the filesystems in read-only mode, but you can force this if you really have to write on EXT4 partitions from Windows (this is not recommended). Using it, your EXT partitions will be displayed just like native NTFS or FAT partitions, being accessible from Windows Explorer.
Fonte: Montar partições EXT4, EXT3 ou EXT2 no Windows 7 Ou XP ~ Web Upd8: Blog do Ubuntu / Linux