Recently, well in the last few years that is, I've enjoyed using references to other works and writers that I've enjoyed before. For instance, in a book due out this year, there's an obvious homage reference to The Day The Earth Stood Still with a remark about Klaatu Baratta Nicto and being surrounded by troops. In another book, I gave the lead character the name of a favorite sf author of mine. In still another, I've been using some vague references to some songs I liked such as titling one as Love and Darkness. Listen to "Southside" for that one. Yes, I've also used the names of some deceased friends for hero characters to kind of give them a chance at immortality.