Dave Winer has written ETag support for . It's currently in testing and should be released soon. He also did a survey of the feeds he's subscribed to, and over 80% of them already support ETag-based get.

Brent Simmons is likewise working on support in NetNewsWire. (and now he's released a beta.)

Kudos to developers for being so quick to tackle a pretty important issue. These two applications account for about 20% of my bandwidth, and a hell of a lot more of other peoples'

And this kudos goes doubly to Aggie, of course, which did the right thing all along.