One of the big concerns in the use open and public data lies around privacy – whether the information you provide and is collected about could be used to identify you personally. While this might be an issue with respect to governmental or commercial entities, where I work we are very rarely interested! It’s the patterns that arise from groups of people that are interesting, and knowing that the datum I’m observing is Oliver O’Brien and he lives in Chadwick Road, Peckham* does little to add to my analysis. Now, knowing that that a data point lives in SE15, has above median salary and reads the telegraph* might be useful for some sort of analysis – but at no point do I need his actual name, and while useful, his address is not necessary. With all this data from overlapping, geographically-coded data, it’s been argued that it’s relatively easy to identify individuals, especially those in a minority (whether ethnic, fiscal, or other). While this isn’t meant to dismiss people’s concerns, particularly wrt to governmental and political organisations and businesses, I thought it worth stating the counter-example. To wit: at CASA, knowing someone’s name and address is useless – but we are interested in information about groups of people’s income, lifestyle etc.
As an example, this is a visualisation of the journey of one London Bikeshare bike on one day last year. As noted previously, we don’t have GPS data (and as far as I know, it doesn’t exist) so the routes we assign are reasonable guesses** – only the start and end points and timings are known. Secondly, we don’t know who was using the bike – that’s also hidden to us. And seeing the “path” of one bike is (I hope you’ll agree) rather interesting, but doesn’t tell us much about the system as a whole, which is what we actually care about.
And because it’s Christmas, this is what Xmas *last* year looked like for the bike scheme:
Some very slow cyclists there, making their way home after too much turkey and Christmas cheer. Merry Xmas, readers!
*none of this is supposed to reflect the actual @oobr. He’s much too cool to live in Peckham, for a start
** by Ollie O’Brien, Open Street Map and Routino
Sociable Physics 
Can you change these displays so that density along certain routes shows up as more bikes use them? can you also do other visualisations where direction builds up along a colour gradient, origins being blue and destinations red and as it builds up with density colours go darker or more intense. So if one bike went from one end of oxford st to the other and then back you would see nothing…. These are great
ah, I only just looked at the next post, being that you cited someone else for the map I assumed that would be a one off about the bike share. Ignore me