IMHO - Radio 4's afternoon play is a good element to include in your day's schedule if you're writing at home all day. Radio makes you feel less guilty than TV (and it is much better). It helps you escape for 45 mins while having a late lunch.

Yesterday's play included brief advice on the best way to oversome writer's block... Listen again here:
http://www.bbc.co.uk/programmes/b00b1ny6

I listen to the radio in the afternoon when I am working in the lab. I have the lab to myself and took a radio with me last year. I have listened to quite a few afternoon plays. Some of them are really dramatic!! :-)