- More Tests!
 - Check if closing input stream does right thing (should close connection after response is written)

- Low level protocol:
 - Authentication (basic and digest)
 - Close connection if resource doesn't read entire input stream

 - sendfile (initial sketch in stream.py, but needs work in twisted, too)
 - Add parsers/generators for the rest of the headers:
  - Cache-Control, Pragma, Trailer, Upgrade, Via, Warning
  - Authorization, WWW-Authenticate

 - Cookies

- Application server:
 - Other useful filters: content-encoding, caching, others?

- Client library *LATER*
  - Convert proxy, distrib
- Internal request submission API
- FastCGI client/server