Yep, Tartan, I've had a play, but I can't say the results are startling. Maybe a marginal improvement.
There are a number of parameters that are interdependent - MTU, MSS and RWIN.
You don't say if you're dialup or some other connection. MTU depends on whether you're using a dialup connection or something else. Assuming dialup, 'cos that's the most common (I think):
MTU should be set to 576.
MSS is MTU minus 40, = 536
RWIN should be 4 or 8 times MTU, ie 2144 or 4288. The Windows default, 8192, is not a required multiple. Sorry, I don't know how you should choose between the multiples. The prog I use to set this stuff says experiment!
There is another setting, TTL. The default is 32. My prog says set it to 64.
The prog I use is InternetBOOST from
www.bonzi.com
I get pretty good results, but I also use SSH and port forwarding, which considerably accelerates the flow of text-based data. (HTML, which makes your browser paint its page, is text and is therefore accelerated.)
Hope this is of interest, and would be pleased to try to help out with SSH and port forwarding if you're interested.
AA