Everyone's talking about Mariah Carey's gargantuan engagement ring, but I'm going to go in another direction and talk about these Singleringen rings that are popping up on other celebrities' fingers. We're all familiar with engagement and wedding rings, but Singleringen is a company that saw the opportunity to create rings for single people. Now many of you long-time readers know that I normally don't promote fashion just because it's being worn by...