StumbleUpon.
Faecbook, as well, but not so much. There's not as much to do on there. StumbleUpon is a potentially infinite time sink.
In fact, I'd say Google Reader has increased my productivity, since once I've skimmed the days articles from Slashdot/TechCrunch/etc, I crack on with some work, and I'm not as tempted to use SU.
In fact, I'd say Google Reader has increased my productivity, since once I've skimmed the days articles from Slashdot/TechCrunch/etc, I crack on with some work, and I'm not as tempted to use SU.