Some of the very best reads are one-offs. This comes to mind: http://www.improvresourcecenter.com/mb/tpcs.html

Blogs: Philalawyer.net, 37Signals' Signal Vs. Noise, Blog Maverick, all the Overheard in * blogs

One-offs: 37 Signals' Getting Real, public domain books including Letters to a Stoic and Walden to name a couple

Lifehacker --> http://www.lifehacker.com

NYTimes --> http://www.nytimes.com

Discover Magazine --> http://discovermagazine.com/

Onion --> http://www.onion.com

Valleywag --> http://www.Valleywag.com

http://www.waiterrant.net

http://www.offthebroiler.com (though it really went downhill when the author started trying to eat healthily)

It seems like there used to be more stuff worth reading on the web, but that's probably just my mental facilities going to hell as I get old (x > 30)

http://www.thedailywtf.com/