I’ve started to port eSTREAM candidate ciphers into the Linux kernel. So far I’ve successfully ported Salsa20. I’m aiming to port SOSEMANUK next. This is a work in progress. A more detailed description of the what, why and how is available here.
Currently eSTREAM is at Phase 3. Hopefully by May 2008 a final selection of stream ciphers will be made and what I am doing now will have greater utility for Linux users then. :-)