According to a series of posts on his DeviantArt page, comic artist and designer of the recent Thundercats reboot, Dan Norton was commissioned by the BBC a few years ago to do some concept art for a proposed Doctor Who animated series.
There has been other animated Doctor Who, but this would have been a full-on TV series, and, if the designs are any indication, would have focused on the first Doctor, and featured appearances from all the others.
Apparently, the BBC passed for fear of diluting the property, though having an outlet to revisit all the old Doctors (and give them a bit of a modern twist) would have been pretty cool.
Bleeding Cool posted a compilation of all Norton’s comments regarding the series, which includes:
Yeah man, we were so close… Had a few revisions creatively that were requested and so we retooled. It was going to be epic man. End of the day, BBC didn’t want anything to distract from production of the tv show.