is it possible? if not pop-up at least let's point out how to be alerted at once

You are free to monitor system log files periodically using scripts and other forms of automation and make them search for specific keywords (e.g. as specified with iptables' --log-prefix parameter).

actually I found very satisfying package - firestarter great capabilities for ToS, ICMP filtering, so many easy to handle rules creation menus like for source you have the option to directly specify - firewall host or range or local , single click enables NAT for local guys, and etc. single click FIREWALL LOCK - deny all traffic, and all that in tiny notification area enjoy some quote


#set up Internet connection sharing in with just a few clicks, or port forwarding when used on a LAN.
# Open and close ports, shaping your firewall with a few mouse clicks.
# Has the ability to restrict outgoing traffic.
# Does advanced kernel tuning stuff, so you don't have to.
# Shows your active connections, including traffic routed through the firewall.
# Translated into over 35 languages.
# Support Linux kernels 2.4 and 2.6.


almost forgot - can set up DHCP server for you with single click again

and what's really the point here is - Real-time firewall event monitor shows intrusion attempts as they happen (also suitable for gateways with ssh could be graphically or console managed)
fs-security.com <- enjoy your safety exept I guess FIN and SYN are not completely covered etc.

but it's not enough for sure download it only if nothing else applicable

or as a partial security measure