Block websites without any software

Steps

1. Browse C:\WINDOWS\system32\drivers\etc

2. Find the file named "HOSTS"

3. Open it in notepad

4. Under "127.0.0.1 localhost" Add 127.0.0.2 www.orkut.com , and that site will no longer be accessable.

example :
127.0.0.1 localhost
127.0.0.2 www.orkut.com

www.orkut.com is now unaccessable

For every site after that you want to add, just add "1" to the last number in the internal ip (127.0.0.2) and then the add like before.
IE:
127.0.0.3 www.yahoo.com
127.0.0.4 www.msn.com
127.0.0.5 www.google.com