"The FLIP cam is one option...cheap and easy, too. "
If that is an option, then the the Kodak zi8 is a much better choice -HD vidoe, up through 1080p, and, these are the clinchers:
1. External mic jack.
2. Manual audio control with meters. Yes, that's right, better audio hardware than most $1000+ camcorders.
$149 at Amazon. Also has (digital) inage stabilization and a macro mode.