Sense.fm's domain registration expired Sept. 16th - oops. That makes their website and streams inaccessible through normal means until they are able to resolve the registry issues.
The good news is that they are continuing to broadcast so if you simply bypass the DNS network you can get around the issue and get your Sense.fm fix.
The easiest way to work around the issue is to add an entry to your hosts file. A quick dig of their nameservers (ns1.webpartnersworldwide.com) shows us the IP address we need is 174.121.134.99.
So we want to add the following to our hosts file:
174.121.134.99 sense.fm www.sense.fm
On sane systems like my Mac the hosts file is /etc/hosts but on Windows it's usually
c:windowssystem32driversetchosts
After you add the sense.fm line to your hosts file just open your browser and visit www.sense.fm like normal.
You're welcome!