I've been doing audio-only with a $40 dictator from Wal-mart that fits in my pocket. It averages 150-200 MB a day. I generate hashes of each file and timestamp them so they're more likely to be useful if I ever need them for proof of something.
The thing that prompted me to start doing this was frequent arguments with close ones that often got down to "you said this", "no I didn't" type of stuff. It's oddly very assuring to have this recording. (FTR, I used it for that purpose more or less once. Although I find it useful for recording therapy sessions too.)
Combine this with speech-to-text transcription software and you get a searchable archive of your recorded interactions!
ETA: In theory. In practice, dictation software algorithms are probably not up to the task of turning noisy speech from different people into text with any reasonable accuracy.
The old idea of lifelogging seems to be a reality now. It has the potential to be quite useful, and not just in distant contrived scenarios like cryonics or being recreated by an AI.
One of the classic objections was that we couldn’t afford to store the many gigabytes - possibly hundreds of gigabytes a year! - such a practice would generate, but right now you can buy 1 terabyte for <$50. And there’s no end in sight to whatever Moore’s law has been governing hard-drives over the past decade or two.
But how is one to record it? That seems to be the rub. All the storage space we could want, all sorts of new formats like WebM or Dirac or x264 to store the videos in - but what camera generates the data in the first place?
We don’t care about sleep time, so we don’t need any more than 16 hours or so of recording a day. We can probably get away with 12. Even 8 might be enough (to record yourself on the job - or off). An encoded compressed video might be 1 megabyte a minute or 60 megabytes an hour, but let’s be generous and assume 15x worse than that, or about 1 gigabyte an hour. So perhaps 16 gigabytes.
16 gigabytes of Flash costs $40 or less. So that’s not an issue either.
And presumably optics and microprocessors are very cheap given the incredible popularity of web cameras, digital cameras, digital camcorders and whatnot over the last decade.
But for all that, I can’t seem to find a mini-camcorder which will record even 8 hours and be a useful lifelogger!
Am I wrong? Are there existing products? It seems to me that it ought to be perfectly possible to take something like the uCorder, slap in $110 of batteries, and get it up to 8 or 12 hours’ life. But I have yet to find such a thing.