Block access to web sites and on-line malware with NxFilter DNS filter
NxFilter is a free, portable and efficient Java based utility that will let you restrict the access of a PC to the internet, exclude site you prefer the users of that computer not to visit.
The program lets you monitor a networks internet traffic and block access to certain sites you can define at will.
Note that the program is not an example of simplicity, but if you devote some time you will learn how to use it without problems, since detailed documentation is also available. Java environment must be already installed on your PC.
A nice feature of NxFilter is that gives you notification on users that tried to visit restricted web sites.