First, you can save every email sent and received, thus covering your ass. (This rationale does not apply to the dishonest, who probably don't want to bear burden of establishing a paper trail).
Second, you can search your email quickly for the CYA email.
Third (and best of all) you can email yourself the full-text of articles and frequently-used decisions, thus creating a legal database that you can search for free.
Go get Gmail.