If you have a laptop you can download an app called PDA-NET annd tether your droid to your laptop. From there you can fire up your laptop using the Droid as your internet connection and watch tv on your laptop and possibly video out from your laptop to your tv.
This is how I watced tv on the go before the Droid app. and it's how I still do it to get better quality. For rooted phones, you can use an app called wireless tether.
Also, the Droid X is coming out next month with HDMI out. Hopefully Slingmedia considers giving the option for HDMI out.
One thing to consider, data rates can be higher than slingmobile.