um....ok I've been on other boards where they totally trashed people on this topic so I'll put it as simple as I can.
Legally speaking with the 1996 telecommunications act the cable co's are a service company and not a product company. With satellites you can sometimes use say a dtv dish with dish network (as long as the receiver is the right one)
In reality though anything beyond a analog tuner is next to impossible to find. Of course sometimes if someone say disconnects cable and loses the box (claims to lose it) they'd be billed and in effect could find it and own it again.
You can use vcr's and pvr's as analog tuners, heck many tv's are cable ready (non scrambled material)
Digital boxes are very hard to find...hd boxes I'm assuming are very very rare. I've heard of satellite hd boxes for selling for $800-1,000 in some stores so in all likelyhood you probably are better off renting!
Ultimatly I'd say in three to four years most cable will go digital. With this in mind anyone with a analog box will have to turn it in...if they own their own they'd be staring at a blank screen.
Another way to describe some of the boxes and so forth is like this. Remember rotary telephones? Technically the phone co's cannot prevent you from using a rotary telelphone. But at this point the amount of services that your blocked off on will cause a ton of frustration. Most co's these days have menu's to press and it will ultimatly time out and hang up if there's no activity.
