Jack M. Balkin, Knight Professor of Constitutional Law and the First Amendment at the Yale Law School, has generously offered a free online version of his book, Cultural Software: A Theory of Ideology, in .pdf format.
I skipped right to Chapter Three: Memetic Evolution, which I found to contain a fine exposition about memes.
Jack is the founder of the fine legal blog Balkinization, and I have read some of JB's posts that I found well thought-out; but until I delved into this larger work of his, I did not fully realize how smart he is. I don't know why I assumed he was a Yalie; but I decided to look into that and found that he is a graduate of Harvard College and Harvard Law School. Now his brilliance is more understandable to me. Jack, I was there in Tercentenary Theater in 1981 with you, brother. Keep up the fine work!
UPDATE: Another great post from JB -- "Has Congress unconstitutionally suspended the writ of habeas corpus?"