There is a comercial product line called X-10, been around 20-30 years, not the expensive from what I understand. Covers home automation and security pretty thoroughly... Might be with checking into, least you might get some specific ideas on what you want to do. Remote control, computer, timers, sensors...
On the web, there are dozens of site dedicated to home automation projects, some do-it-yourself, some selling (stuff). Home improvement sites also have automation projects.
Not really a big interest to me, be I run across these things often while looking for semi-related information.