Well this one:
because it's provided me with the incentive to do a blog-a-day challenge, and is inspiring to read too.
This blog is by someone I am in a Facebook group with - and train together in our group SSS sessions. It's nice to read a blog of someone you also interact with in person as you get a better picture of them :)
The third is difficult, there's a few that I've been reading adhoc (or as part of the blog-a-day challenge). I'm going with one of the first blogs I found when starting the program - although she's been a bit quiet recently. Apart from standard blog posts there are recipes there too.
I really enjoy reading other people's experiences of the program.