The Unbound Doctors - Geoffrey Balydon, David Warner, David Collings, Derek Jacobi, Arabella Weir, Michael Jayston (2003, 2005, 2008)
For the fortieth anniversary, Big Finish did a series of audio stories with the "what if...?" question. Things like "What if the Doctor never left Gallifrey?" or "What if the Doctor's exile to Earth was in the 1990s?" or "What if the Doctor was a drunken supermarket employee?" They cast the roles and went for it, producing something that was nothing if not ambitious. I haven't listened to all of the Unbound audios, but the ones I have heard, I've enjoyed. David Warner, in particular, makes for such an excellent alternate Third Doctor that one wonders why he was never offered the role of the Doctor for TV (or the role of the Master, come to that). Arabella Weir's story is also quite excellent, if you've ever wanted a female, alcoholic Doctor who enjoys watching the X-Files and gets harassed by an elderly Time Lord in disco gear and voiced by David Tennant. Sadly, the series didn't sell well enough for Big Finish to continue on, and that's really a shame. But at least during its brief time they managed to find a way to use one of the more sinister Doctors-who-wasn't; the Valeyard. http://www.youtube.com/watch?v=EZygnwgzJaM