Geotagging, geocaching, plot your runs, trips and so forth. There are many new coming hobbies and tendencies provided by new technologies such as GPS devices, interactive online maps and various web apps. What about just plotting your entire life?
I wanted a more efficient way to geotag photos, and a lot of people are doing it by comparing a GPS log with the photos EXIF timestamp, and adding the GPS data as EXIF data to the photos. Often by interpolating between the GPS points, to get a closer match.
But the log itself could become a little amusing, especially on vacations, to see where you actually have been. Not to mention those Sundays, where you wake up and think “hmm… what exactly happened yesterday”. Upload the log to your nifty little web app, and there you go. In 15 years, it could be possible to look back and see where you were on the19th of April 2008, or any date and time for that matter. You can then calculate stuff like how many meters you moved overall for 2008, or what was your average velocity in 2011, compared with the year before. If I ever become so manically obsessed with tracking my own whereabouts at any time (quite likely), I would prefer to keep all this data somewhat private though. That being said, I am really not too concerned about privacy in general.
Anyway, for my new toy, I just ordered this:

I wanted a small lightweight logger at first, to see if this would catch my attention. So by studying the flickr group “GeoTagging Flickr”, to look for advice i found the DG-100 GPS Data Logger to be an interesting choice. This gps receiver should be more precise than the Sony GPS-CS1, and have a newer chip set :O! I am a little nervous about the battery time though, but for a first device whatever must be adequate.
Logging and uploading daily whereabouts will only be step one. When GPS phone prices drops, it could be tempting to write a little java or whatever app, that sends the GPS data directly to a server. In that way, it would be possible to obtain real time life logging, which obviously has tons of opportunities (?!).
In a few years, I image myself with a large hat, which transmits my location and my viewpoint video/audio feed to my server, so I always have an exact multi media log of my life… Well, maybe not.
Other than private amusement, there must be great marketing potentials if GPS logs where publicly obtainable. Even for semi or fully anonymous data. It would be possible to use the data to define marketing segments, and target ads about local shopping or dining specifically to people who is likely to get near these areas. By generating heat maps, it could be possible to forecast trends to where the new hip spots are occurring. It could also be used to optimize transportation, city planning, real estate location relevance and much more.
More on this topic when I actually make an implementation and try it out.