[magicalhippo]

I use no-ip as dyndns for my home ip, so I can log in at home from outside. Recently at work my putty failed to connect, so I figured my internet line was down, it happens.

Came home, internet works fine. Everything looked just fine.

Back at work next day still can't connect. So I tried pinging, and I immediately see that the ip my home hostname resolves to is not what my ISP has. So I go to nslookup and try a DNS server I know (another local ISP), and it resolves to what I expected.

A bit of checking later I find that at work they've started using OpenDNS, and OpenDNS has blocked all of no-ip due to malware and spam.

So yeah, could be relevant.