Grew up a Rangers fan but, when I moved to England for University, realised just how disgusting the bigotry was. Supported St Mirren then as they were my closest team but they never really did it for me. I had moved to Inverness and liked Clach but when the merger happened, ICT became my main team. As it was, ICT's first match was against St Mirren, so had to declare my allegiance straightaway.
Living in Egypt, I also support Ismailia. They're like the Aberdeen to the Old Firm of Zamalek and Ahly.
In England, I've also flirted around the teams. Notts Forest (success) and West Ham (family) as a boy, then Everton as they seemed full of Scots. Also, follow some teams due to their players or manager (e.g. Matt le Tissier, Paul Sturrock's Plymouth)
Chris