In this tongue-in-cheek article on The Morning News, Graham T. Beck explains what your email greeting says about you -- and not a single one is the right way to go. I usually start with Hi, which reportedly implies that I think I'm important (so right you are, Graham! So right you are!).

Some other examples:

"Bro," makes clear that the last time we saw one another was in the neon glow of a Jägermestier tap machine, and you were selling grams of baby laxative, so I will not be coming to your birthday party at Poughkeepsie's newest hotspot, the Infamous Scandalous Lounge.

"Greetings:" denotes that I signed up for your dreadful boutique's mailing list in hopes of impressing somebody in the store, and now I resent all of the parties involved, myself most of all.