Q:

Time of another machine

In c# when we use DateTime.Now the property value is current date & time of local machine
how can get the time of another machine with IP address or machine's name 

A:

You can achive by writing a service that gives you the current time? or connecting to remote machine and sending some wmi query
Similar question: http://social.msdn.microsoft.com/forums/en-US/netfxremoting/thread/f2ff8a33-df5d-4bad-aa89-7b2a2dd73d73/

