Pipelining is turned off by default in Knoppix's IceWeasel.
I've turned mine on by entering about:config into the browser address line,
promising 'to be careful', and changing network.http.pipelining to true.

Most sites seem to come up faster this way for me.
I'm wondering what the down-side may be in actual practice.
Opera is the only major browser that has this parameter set to true by default,
according to wikipedia. http://en.wikipedia.org/wiki/HTTP_pipelining

Open to any comments, advice, warnings from those having some first-hand
experience in this area, either good or bad.