Wired published an interesting story about Jaap de Maat's final year project - the finale to a two-year-long MA in Information Experience Design from the Royal College of Art.
The design is basically an old filing cabinet that follows visitors of RCA. It's called 'I know what you did last summer'. It's about the traces in the form of digital information we leave behind with our activities in the digital world:
"It is physically impossible for the human brain to remember every event from our past in full detail. The default setting is to forget and our memories are constructed based on our current values. In the digital age it has become easier to look back with great accuracy. But this development contains hidden dangers, as those stored recollections can easily be misinterpreted and manipulated. That sobering thought should rule our online behaviour, because the traces we leave behind now will follow us around for ever."
While in the old days physical information could be destroyed this is harder to do in the digital world(s). So we should take a great care what traces we leave behind.