There is one for ext2, but does not read journaling portion ext3 with that. So some data may not be seen. ext2ifs http://uranus.it.swin.edu.au/~jn/linux/ext2ifs.htm
Now there should be no reason why you can't use the ntfs-3g under the Fuse interface. Their claim is it is 100 percent safe to read and write to ntfs. If there is ever a problem they want to know.
Can't see why fat would be a problem at all. You will lose some attributes of a file when they are placed on fat32. But if all the data is things like docs, music, videos then I see no problems there. Granted Windows can't create on larger than 32gig it can read and write to ones larger. Just have to use linux to create it. http://www.allensmith.net/Storage/HDDlimit/FAT32.htm