Oh sure, I'd reply back, knowing full well this is The Internet.
If there were a device which could deliver a punch via TCP/IP, it'd all ready be in use a Ross the globe. Thankfully we can't physically assault someone over these channels, you've gotta accept some responsibility and swallow your spot now and again.
If you can't handle someone calling you a cunt out of the blue, then maybe it's time to log off for a while.