A Time-Space Visualiser was a device that allowed the operator to view any event in history. The First Doctor and his companions used it to observe Queen Elizabeth I and Francis Bacon meeting with William Shakespeare, Abraham Lincoln delivering his Gettysburg Address and the Beatles performing "Ticket to Ride". The Visualiser later showed them the Daleks launching their time machine on a mission to exterminate them, which let them buy some time. Much later in the Doctor's life, Izzy Sinclair used it to play video games on — games which involved avatars of the Doctor's past lives.
We like tracking our technology round these parts. Only problem is that the show is about a time travelling scientist. And he's spawned shows like Torchwood that are entirely focussed on alien tech. So there's a lot of tech sittin' around the joint. Be bold, though, and start your journey at category:technology.
When looking for a piece of technology on this wiki, it's helpful to think about some of the broader categories. Looking for the tech of a certain species? Go to technology by species.
The DWU likes its sonic tech, doesn't it? But it's not just the sonic screwdriver you have to keep an ear out for. Don't forget, the Ice Warriors and several other species are heavily invested in sonic technology, which you can find at category:sonic devices.
One of the broadest classifications of technology is communications technology. Since the series is about a guy who likes to talk a lot, we figure that only makes sense!