I think the easiest way to acheive this is to use the Charron module, or some alike. They are plug and play, and you control them with simple Serial command. You can even use Hyperterminal for that
http://www.hw-group.com/products/charon1/index_en.html
they also provide some code example for various PC language.

Sure enough there's more than charron one on the market, but I don't know... really need to refresh my stock for that one day...before
http://free.timeanddate.com/countdow...05-21T18:00:00
Time goes by too fast