quick incoming connection blocking

hi guys.

does anyone know of a program that I can use to quickly block an incoming connection from a specific IP and then just as easily re-allow that IP to send requests?

i mean, theoritically, i want to be able to copy an IP, paste it into a nice little textbox, click block, have it show up in a list, add a few more, and then click a box that says allow next to an IP that i want to re-allow.

thanks in advance :).

i was at first referred to peer guardian 2, but that's not really as described above.

use your firewall