Grim Fandango has got lots of great ones, but my brain's memory banks are pretty tired today.
Indeed, thankfully there's whole qikiquotes and stuff out there. But basically every chat in GF is filled with life's (death's?) little truths, stuff like:
As a rule, I never touch anything more sophisticated and delicate than myself.
"Nobody knows what's gonna happen at the end of the line, so we might as well enjoy the trip"
Always liked that one.
Also TLJ, courtesy of wikiquote:
April: How can you do that? How can you remember every story ever told?
The Teller: The secret is to tell them often, and to tell them in your own words, not the words of your ancestors.
April: Doesn't that mean that the stories change with every generation?
The Teller: Yes, as all Tales must. Change is important, otherwise the Tales will have no meaning to us... They will be just words, and we do not care about the words. We care about what the words tell us.