KAT5 units would be one obvious choice, and there's a forum here on Automated Home
The KAT5 website is www.kat5.tv and you can buy from www.laser.com.
Basic info & features desciption is here: http://www.kat5.tv/modules.html
HTH,
Tim.
(p.s. I've no connection with them, but they've had lots of good feedback on the UKHA mailing list)