That is what I do, I have a 4 character personal salt, like "7Pd$", and put it in the middle of a lowercase word or phrase. Having a symbol, lowercase letter, uppercase number, and number will satisfy most password requirements. I use it on many sites, so it is easy to remember. It also makes it simple to write passwords down, e.g. "correct horse ^ battery staple" which means to me "correct horse 7Pd$ battery staple", but would not be useful to someone who saw it, since they don't know my personal salt. A combination of what xkcd said and a short personal salt that's easy to remember is probably best.