In 1982, the much-loved and sadly now defunct BBC TV show Tomorrow's World took a look at "one ordinary finger and one rather extraordinary TV screen." The result are touching, in more than one sense of the word.
Marvel, as this chap's finger renders ASCII text onscreen before your very eyes. In fact, as is explained in the video, this was one of the first IR touchscreens, which measured where your finger was using beams of light rather the resistance or capacitance within the screen. Remember them? Things get even weirder when he gets to possible applications, though — but I won't ruin that surprise (spoiler: it's not an iPhone). [BritLab]