connect my HDTV and computer without ethernet

I only have a coax cable in my rented house. I can't make holes in the walls. I'm strongly opposed to any type of wireless connection due to radiation (Don't want my kids to suffer in the future). Is there any way to connect my HDTV and computer without ethernet if they are in the different rooms and these rooms are connecte with a coax cable only?

Actiontec Ethernet Over Coax MoCA Adapter can use existing coax cabling (like cable TV coax cables) to create point-to-point and point-to-multipoint network configurations.

[skwlsout]

How about Homeplug? Networking over your mains power cables. Works quite well.