For those of you who own a Roku device this might be good news. I'm not sure how long the has been available, but I discovered it the other day.
The Roku channel itself is a free download. Kimba and Astro Boy are both available, and both are English dubs. You can either watch episodes for free with ads, or rent it for $0.99 with no ads. The quality is fairly good but varies depending on the strength of your internet connection.
Thought some folks here would be interested!