Apache disables Nagle by default, which is what you want for small static files, but I'd love to see data showing that Nagle is actually a significant performance issue for a realistic load.
You're right about Nagle; I mention it only because lighty or one of the others does not turn it off by default.
Having a lightweight proxy that keeps connections alive on the client end but cuts them off between themselves and the application layer is the bigger win all round for many real-world web loads.
