DNS hijacking has become common place, not just used by rogue DNS servers anymore, but seems like most (all?) Internet Service providers are now resolving non-existent domains to the ISP's own servers.
This is very irritating, and causes numerous problems - where a NXDOMAIN response is expected, applications now get a valid response. RCN puts up a search page, which contains search data, and does not even contain a link to the address actually typed. All so the ISP can serve more ads to the end-user. And RCN has no easy way to opt-out that would work for all applications and operating systems.
So users have turned to many different methods: installing browser plug-ins - poor solution since all non-browser applications won't see the fix, or using Public DNS Servers and configuring their DNS lookups to go to these Public Servers.
But now, even the Public DNS Servers are involved in subverting NXDOMAIN responses - they too want to serve ads and issue redirects. A web search on this issue results in many people saying that OpenDNS has fixed their problems - which is not really true. It is in fact, quite complicated to figure out what the basic, free, OpenDNS really does, and it requires jumping through many steps to make it stop the hijacking - they claim it can be done, but requires registration, etc. They do offer other services, which may be useful to most regular users - such as security features, but they are certainly not providing easy access to non-hijacking DNS servers.
Just last month, turns out that there is one public DNS service that promises to Get the results you expect with absolutely no redirection. - Google's Public DNS.
Finally! Now this does require giving Google even more information than they already have, they already have gobs of data on every man, woman, and child on this planet, and this gives them one more hook - Geez, Google Wants to Take Over DNS, Too sums it well!
But unless you are willing to roll your own DNS caching server and keep that machine running, it is much easier just to use the public DNS servers - so, in your cable modem router, change the DNS settings to use Google's DNS Server instead of automatically getting them from the ISP: use IP addresses 18.104.22.168 and 22.214.171.124 as your DNS servers.
Life is much better now. Especially for those who have computers that use VPN to connect to corporate intranets intermittently. Now don't have to worry about messed up redirects from the ISP and re-typing long urls.