First, credit where credit is due. My tip is similar to evanhahn's Friend Relationship Management post here: http://www.rememberthemilk.com/forums/tips/11137/
A few extra things I do:
I've added everyone in my LinkedIn network, all my old coworkers, old friends, etc using RTM's import email address, then multi-edited everyone once in RTM. I add any one new right after our first meeting. I'm keeping CRM-like notes in Notes when I communicate with someone, and making notes for what specifically to ask about or report back on when I reach out next so I don't have to waste time re-reading emails or trying to remember what they said or were interested in. I've got the tasks set to repeat after x depending on scope of relationship, etc (usually between every 3 to 9 months). Task name is "FirstName LastName (company or school where I know them from)," and tagged ".people". This makes it easy to find everyone from various groups.
Hope others find this helpful!
Posted at 4:13pm on August 25, 2012