Yes, I would say if you are really a home theater enthusiast, then you definitely need this.
This cable allows you to customizable your universal remote control. JP1/JP1.2/JP1.3 is a process that you can use to re-program your UEI remote (ie, One For All and Radio Shack brands) from your PC. Not only does it allow you to manage your macros, etc in a much easier way than doing it on the remote itself, it also lets you overcode some of the silly restrictions that are programmed into these remotes and it lets you add upgrades which let the remote to control devices it would not otherwise control.
There is a great article on JP1:
http://www.tiaowiki.com/w/Hacking_JP1_Remotes
The JP1 is now an old protocol, UEI replaced it with JP1.2/JP1.3 protocol. If you have a newer remote from UEI or Radio Shack, you may have a JP1.2/1.3 remote.
We have some tutorials here:
http://www.tiaowiki.com/w/JP1%2C_JP1.1%2C_JP1.2_and_JP1.3_Cable_for_Remote_Control_Tutorials
and more information on
http://www.hifi-remote.com
- Regards