I have one of these Omnifi myself. I bought it in one of the woot.com bundles a couple years ago. I really like it. Be forewarned though, it doesn't do anyhing other than 802.11b. I prefer to use a wired connection. It tends to skip if you're flipping through options while playing files encoded higher than (I think) 256Kbps. I.e., no lossles music through this.
All things considered, it's pretty cool and if you buy it - definitely sign up for the Yahoo groups Omnifi group to see some of the hacks that have been done w/ it. You can cycle through music and pictures on your TV, but that's as far as it goes.
There are currently better options out there, but you have to spend more than $20 for them.
Also, I noticed that Car audio is mentioned in this thread. This isn't the Car version. The Car version is a DMP1, not the DMS1.
Hope that helps!
**edit** if you keep your eyes open, you can occasionally find one of the old slingboxes for around $50 + Ship. IMO, that's a better option even for more money.