My interest was sparked off by a tree given to a cousin of mine by a double cousin(Macdonald/Sinclair) of my mother's, which was only of my Sinclair line. I got a copy of the tree, but, at that time, did not have a computer.
Once I had the computer, I decided to research my MacDonald line, then my paternal ancestry, and, from there, am currently up to 5000+ connections. Some are very distant at the moment, but I live in hopes that eventually they will connect at a more direct level. as my son, who has lived and worked in Caithness, says "I think Adam and Eve originated here, and their descenadants are still inter-marrying away. Everybody in the world has their origins in Caithness!"
It has become an addiction!