Http://www.tomshardware.com with proxy only

Most likely it has to do with the automatic IP routing that our network is set up with. Will look into seeing if there is a better workaround for you.

the same Problem with http://www.tomshardware.de, only reachable with proxy
I just can reach http://www.tomshardware.co.uk

Are you behind a restrictive firewall or another application that restricts certain websites? A traceroute might be helpful, if you'd like to send one in to me at jpishgar@bestofmedia.com.

no, just the Windows Firewall.
I sent my traceroute to you.