Question: can a outsider person block a particular site on someone else's computer without having the physical access? 

Answer: I do believe this can be done if the person knows your IP address and controls the site you are trying to access... this is what is done when people are banned from Chat Rooms.. But otherwise I do not believe they can stop you accessing a remote site.\n\nTry the Link below if you wish to access... it lets you surf with a Random IP Address\n\nhttp://www.anonymization.net/
This question from the Yahoo Q&A forum is categorized in the topic: Computers & Internet