[setishock]

Having been in the electronic security field for 25 years, I think I have a handle on what you're wanting.
You want offsite real time recording to back up the local recording.
The main issue is bandwidth usage that hosts charge for. You only get so much per month for what you pay. When you burn that up they have the right to shut down your connection. And most will with out hesitation.
Now if you look on the local system and see how big the files are for your recordings you can understand why there are not any companies that do that. Imagen if you record 4 or 5 gigs in a 24 hour period(depending on quailty settings), and multiply that times 30 days times 12 months, that's a whole lot of gigs. It's not storage that becomes the issue, it's the bandwidth you burn up. And having to have a dedicated connection to your work computer is going to be pricey.
You could however do it yourself.
Log in to your dvr from home and use a screen capture program. Media Encoder 9 is free from Microsoft and does a great job capturing the screen. You can set the quailty of the output file and just let it run till it runs out of drive space.
I hope that helped you or gave you some ideas. If you need help with Media Encoder I can be found at computervitals.com.