[TheOne01]

Wasn't sure if this has been discussed, but this was released last week, and it features advanced multi-touch gestures like Pinch zoom, Double tap Zoom, Flick scrolling & Panning. Best of all, it's free!

Adobe� Reader� v9.0.0 Application for Android | Productivity

[Air Force One]

Yeah I downloaded it as soon as I saw it. It's great. I paid for the Beamreader pdf reader a few months back and now regret it as it does not have pinch to zoom. Adobe rocks.

[Duvi]

I think it came out along with the Flash Player that you can d/l with FroYo.