With a pair of servers I have replaced my set-top DVR, and I have a ton of new features.
This began when the very expensive bulb went out on my projector after I gave away my regular TV. Now, to see the shows I usually watch, I have to download them to storage on a Linux server and stream them to my laptop via my home network. At first, this was a manual, annoying, time-consuming task. Then I found Videora. I find this to be so flexible and the quality very acceptable, I may take my cable DVR back to the cable store.
MythDora 4 Linux distribution with a special interface card records my shows off of cable (in HD). I watch them and share them on the internet using the BitTorrent protocol with Videora from a Windows machine with a drive mapping of the /video partition on my MythDora box. Videora downloads content via RSS subscriptions to BitTorrent seeds for the types of content which I would like to watch, whether my cable provider has it or not (including hockey coverage from Canada and Britcoms). Videora content is stored on my MythTV server using drive mappings, so I can watch the shows on my laptop, either by using the MythTV Player over the network, or by copying the show onto the hard drive and using some other MPEG2 player.
I'm modifying an XBox to run a MythTV client that will work on a regular TV, so when I get a replacement bulb for my projector, the modified XBox MythTV frontend menu will be the interface. If the quality from the XBox (720p max) isn't great, I'll go get an HDHomeRun box (1080i). If the TV networks figure out Videora for distributing their shows, the cable folks will be out of the picture. Furthermore, with the MythFlix plug-in, my NetFlix movies are downloaded over the internet and appear on my MythTV menu. Being able to request movies and watch them a while later is just great! The ability to just pick a hockey team and watch every game on my own time using Videora's Season Ticket feature. . . also great! If I start watching more internet stuff than regular cable, I may be able to cut my cable bill down by a lot by just getting really fastinternet only, but I'm not sure I'll be able to completely replace the content I get via cable TV. I'd like to add more storage. Having my music collection on the same menu system with my TV shows is so sweet! The greatest benefit is I can burn DVDs of shows I might want to watch again or take on the road. The second greatest benefit is that I have all my media on one central server and I can watch, pause, and rewind live or recorded shows from any computer or TV (with modified XBox or HDHomeRun) in my house, including laptops over the wireless network. I can watch HD shows on my laptop screen out on the deck, in the garage, or in the tub. Commercial skipping is one or two button presses and it's instant.
I haven't tried it yet, but I should be able to configure TCP ports on my router to allow me to use a web browser to look at my program guide and schedule recordings from any internet connection. With the MythStreamTV plug-in, I should be able to watch shows from my media server over the internet at a lower video quality, as well.
AppleTV + iTunes OR BeyondTV + Cable/Satellite do the same thing, but with fewer features and choices. I think I prefer the more Internet-centric BitTorrent and NetFlix approach. To be able to combine Internet delivery plus cable PVR with one menu system accessible from any screen is a dream come true. You can put your photos on this thing, too. TV has come to the computer network and it's here to stay.