A few bloggers in the MidWest USA region - apparently AT&T DSL customers - are reporting inability to access Blogger, Blog*Spot, and in some cases, various Google services.
We have a Problem Rollup question in Blogger Help Forum, where the epidemiology of the problem is being explored.
For right now, if you are affected by this outage, please use a proxy server to access all Blog*Spot blogs. And read BHG Resources: My Blog Is Gone, or [FAQ] I Can't See My Blog. What Should I Do? for insight into diagnosing this problem.
(Update 10:00 3/28): This problem has been resolved.