[minopret]

You can use 7zip to archive, compress, and AES-256 encrypt.

You can also use GnuPG or openssl to encrypt a file or a disk image.

Lately I took a look at actual filesystems for cross-platform use. I didn't find a great one, but depending on which OS you want to burden with an extra driver, pretty good ones include exFAT, NTFS, and UDF specifically version 2.01. Like you, I am curious whether better answers are available.

[TheLoneWolfling]

Again, those don't work for filesystem purposes. One of the nice things about TC is that it not only is cross-platform, but that it functions as an mountable directory across all of them.