I finally got my speed issues sorted last week -- it looked like *everything* was being throttled apart from HTTP.  Now most things are a bit more reasonable -- but SSH is still throttled down to a megabit or so.  I'm on Naked DSL, not AYCE.  As an aside, the first time I called up to complain they said they don't rate limit, or at least no more than other ISPs -- as far as I can tell this is utterly untrue.

When I got the call to say they'd fixed it (goodness knows how they broke things in the first place), they told me to ring back within 48 hours if the problem was still there.  Did some testing, over random TCP ports speeds were pretty good, no longer that throttled 1 megabit I was getting before.

But SSH was still slow.  Even just shoving random data down port 22 (not SSH at all) was still being rate limited.  So I  called them up to ask.  Once I managed to get the first level support to understand what SSH was, they went to talk to someone higher up and came back with the response of the century:

SSH is peer to peer filesharing, so it's deprioritised.

Idiots.

I'd switch ISPs in an instant if someone else offered free or cheap off-peak traffic.  At least my connection is tolerable now.