One tip that's helped me: when something makes you feel good, add it to feelgood.txt. Over time, you'll start to see patterns (vs. the random, fallible memories/ideas we have about what makes us happy).
Every few days or so I'll have a random entry [7/23/09: felt good to chill with Andreas. played games, chatted, had bfast, etc. hospitality. nice to catch up. 7/15/09: Felt good to 1) post to BE and 2) exercise today].
Looking back, I can see what actually worked in making me happy.