But few Orient fans actually chose to be so of their own volition - especially if they already support a decent Premier League team. But Adam Michie, author of the new book Orientation did exactly that.
Spurs fan Adam had become disillusioned with the Premier League and frustrated that his support of the club wasn't shared by his friends. Seeking a more collective experience, he and a handful of mates agreed over what presumably must have been enough alcohol to kill a herd of mammoths that they would buy a Brisbane Road season ticket.
Fortuitously for them that season was 2010/11, and the book follows the Os through the highlights of that wonderful nine months: the FA Cup run; Jonathan Tehoue's goal against Arsenal; Ryan Jarvis's last-gasp winner against Peterborough; Paul-Jose M'poku's goal against Oldham and many more.
For reliving those great moments, the book is worth a read. But over and above that it's a warm, witty and entertaining tale that will resonate with any football fan - the highs, the lows, the loved one that doesn't understand why you absolutely have to be at a Johnstone Paint Trophy replay on a freezing Tuesday night. (One mid-argument line in particular will resonate with many fans: "The dates of football fixtures were not my fault.")
Incredibly, even after last season Adam remains an Orient fan. The club has put him through a lot. At least do him the favour of buying his excellent book.
Orientation by Adam Michie is available from Chequered Flag Publishing
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