You use any torrent client (like utorrent) and apache
You turn on apache and utorrent at the same time and httpd.exe starts consuming 100% CPU
Then this is for you
There are trackers that are redirecting all tracking traffic to yourself (127.0.0.1). That is redirected to httpd.exe who is waiting for that traffic. utorrent can send +- 200 scrapes/announces per second, that means about 40 per second to your server.
Try doing in cmd.exe (don't make me explain how to get to the cmd.exe):
It'll show that the ip is 127.0.0.1
That brings us to the solution.
In all torrents you download remove the folioing trackers that match:
tracker.zerotracker.com -> (this means http://tracker.zerotracker.com/announce, http://tracker.zerotracker.com:80/announce, etc...)
http://www.sumotracker.com -> (this means http://www.sumotracker.com, udp://www.sumotracker.com, etc...)
and substitute these trackers
tracker.thepiratebay.org, vip.tracker.thepiratebay.org, etc... by: udp://tracker.openbittorrent.com:80/announce
Your problem should be fixed by now. if not, well... there may be more servers that point the DNS towards your own PC.