I've been playing a bit with Twitter' mashup apps during lunch break : Twittervision and Twittermap. Just amazingly simple tools for displaying any geotagged data on a map.
For those of you who ignore what Twitter is, read this recent post by Guy Kawasaki and follow its links.
post-scriptum : as I'm going to be busier (if running at 120% is possible ;-) over the next couple of months, I'll post more twitters here, thanks to Twitter's SMS feature. Watch the left side bar for updates...