Slingbox is very slick. If you have someone in the DC area who is willing to host one for you, it would be a great investment.
There are 3 Slingbox models: Pro, AV, & Tuner.
Pro is the HD version. It's got all the bells and whistles. It can handle multiple devices. I don't know if this one can act as a 'Tuner' (see below).
AV can handle only one device at a time. It can control a cable or satellite box via an IR blaster (comes with it). No tuner functionality. It has A/V and S-video inputs.
Tuner is just that - a tuner. You plug a coax straight up to it and it streams the channels (either cable or off air). If you don't have a cable or satellite box, this is the one you want.
In order to watch the Slingbox remotely, it must be connected to the internet. You must forward a port to your Slingbox via your router. You must also know the IP address of your router. I've watched my slingbox with a speed as low as 256kbps and its viewable. It's not a great picture, but it's better than the alternative.
Here is a screenshot of mine. I have about 800kbps upstream at my house. I am watching it via a T3 at work.