1 TCP Optimizer Description: The TCP Optimizer is a free, easy Windows program that provides an intuitive interface for tuning and optimizing your Internet connection. There is no installation required, just download and run.
The program can aid both the novice and the advanced user in tweaking related TCP/IP parameters in the Windows Registry, making it easy to tune your system to the type of Internet connection used. The tool uses advanced algorithms, and the bandwidth*delay product to find the best TCP Window for your specific connection speed. It provides for easy tuning of all related TCP/IP parameters, such as MTU, RWIN, and even advanced ones like QoS and ToS/Diffserv prioritization. The program works with all current versions of Windows, and includes additional tools, such as testing average latency over multiple hosts, and finding the largest possible packet size (MTU). The TCP Optimizer is targeted towards broadband internet connections, however it can be helpful with tuning any internet connection type, from dialup to Gigabit+ :) see ttp://www.speedguide.net/downloads.php
Also Hack the max half-open TCP connections - If you are on XP sp2, your TCP connections are limited to a maximum of 10. This might hurt your downloading speed because it wont let you connect to as much peers as you want. It is supposed to slow down viruses because their spreading strategy is to connect to a high amount of ip numbers, but it could cripple your torrent downloads. A nice way to fix this is to use this patch inluded here from from http://torrentfreak.com/evid4226patch223d-enzip/
2 Visit also http://torrentfreak.com/optimize-your-BitTorrent-download-speed/ http://groups.msn.com/CanadaToday6/p2ptorrents.msnw for more Bit torrents info ..