Not the usual celebrity tripe, but interesting or informative ones.
Like when we were driving to Kelowna in November, I actually found @DriveBC to have more useful, frequent updates than the radio (thanks in large part to other travelers tweeting weather reports!).
I also found @ShawSupport to be WAY faster responding than either their online chat, or phoning in. I've heard of people experiencing hold times of two hours for internet support... when I got my new modem/router and needed it switched to "gateway" mode, they had it done in 15 minutes.
@NewEarthquake is fascinating to follow too - "GEO-tagged world earthquakes magnitude 4.5+ and tsunami warnings. Dynamic avatar shows last earthquake. Sources: USGS, NOAA, GEOFON." Amazing to see just how active this planet really is...
