Things My Girlfriend and I Have Argued About is one of the funniest web pages I have ever seen and a good read for anyone preparing for marriage. (I think I'm still preparing for marriage despite having already gotten hitched in October 1999.) Although the author and his girlfriend aren't married, they have been together for 13 years and have 2 children, so I suppose it's a common-law marriage.
By the way, my own marriage is not as bad as the relationship described on this page, but I can certainly relate to a.) the pettiness of the arguments and b.) the disproportionality of the effort expended on the arguments as compared to the subject matter. Also, my husband sent me the link, so he thinks it's funny too.