I've wanted to do the same thing with my online activity as well. Chat logs especially. They tend to go into a void and finding an older log is weirdly difficult. I've wanted to log everything and then be able to apply better search algos (semantic search perhaps) to try and make my chat logs useful.
Cellphones are placed amazingly well to provide this sort of search. Seeing the post about BeOS and its amazing metadata-driven BFS filesystem yesterday really makes you think what might have been had iOS and Android been more ambitious about filesystems instead of just re-applying the same old conventions from our desktop computers.
You should be able to just text search every phone call you have made on iOS/Android, today, similar to the automated voicemail transcription features already present etc etc.
