This is my best attempt at gathering together a list of streaming links (mostly from youtube) to additional Doctor Who material, not included in regular broadcasted episodes. It focuses on the new (aka 2005 revived) series, and contains only canon(-ish) material. In other words, things like outtakes, interviews, behind the scenes shenanigans, and hilariousity David Tennant created with the aid of divine inspiration and perhaps an alcoholic drink or two (helllooo and hello) aren’t included. Please feel free to add on anything I may have missed.

• Doctor Who and the Curse of the Fatal Death (1999 Comic Relief Special written by Steven Moffat; Stars Rowan Atkinson, Jim Broadbent, Hugh Grant and more as the Doctor)
• 2005 Children in Need Special (the immediate aftermath of Nine’s regeneration into Ten)
• Attack of the Graske (2005 “interactive episode”, starring Ten)
• Time Crash (2007 Children in Need Special; The Fifth Doctor meets the Tenth)
• 2007 Comic Relief (Lauren Cooper’s new teacher looks a bit familiar)
• 2007 Extras Christmas Special (short scene with Ricky Gervais playing an extra on the show, opposite Ten)
• A Ghost Story for Christmas (companion to Blink, narrated by John Barrowman)
• Music of the Spheres (2008 segment of the BBC Proms, starring Ten)
• 2009 Tonight’s the Night Special (utter ridiculousness with John Barrowman and David Tennant)
• The Wedding of Sarah Jane Smith (The Sarah Jane Adventures 2-part episode, featuring the Tenth Doctor; note: He doesn’t appear until the very end of part 1)
• Meanwhile, in the TARDIS - part 1, part 2 (series 5 dvd features, starring Eleven and Amy)
• Death of the Doctor (The Sarah Jane Adventures 2-part episode, featuring the Eleventh Doctor; note: He doesn’t appear until the very end of part 1)
• 2011 Red Nose Day Special - part 1, part 2 (stars Eleven, Amy and Rory; Timey-wimeyness, slapping and self-flirtation happen)
• 2011 Children in Need Special (Eleven is naked now. Nakedness is cool.)
• Nights with the Doctor (series 6 dvd features, starring Eleven, River and Amy, plus one with Craig, Sophie and Stormageddon)
• Deleted Scenes -
• Army of Ghosts
• Series 3 (part 1, part 2, part 3, Human Nature - basically a Tennant improv)
• Series 4 (Voyage of the Damned, The Fires of Pompeii, Planet of the Ood, The Doctor’s Daughter, Journey’s End)
• 2009 Specials (The Next Doctor, Planet of the Dead, The End of Time)
• Series 5 (The Hungry Earth, The Big Bang)