Ethernet or telephone?I have now two Tivos below my telly.
Any adapter available to split the cable at that end, rather than run two cables around the living room.
Phone, you just need a splitter.
Ethernet - something like this at each end of a single cable. (I'm sure cheaper versions are available..)
Edit: Duh. I should read the post title. Unplug the RJ11 from the Tivo. Plug it into an RJ11->BT socket adapter. You can use a spare ADSL filter, using the modem & phone connectors and leaving the plug dangling. Plug a standard phone double adapter into the phone socket. Plug second tivo into one side and new modem cable connected to first tivo into other.