Just in case you were thinking of buying one of those 40 iPhone 4s that were most likely looted in the UK riots and put on Craigslist, don't—UK networks are blocking all stolen phones, so they'll be worthless.
Losing your phone sucks. Like really, really sucks. Sure there are apps that'll try and find your phone, but still, it sucks. Mobile security firm Lookout analyzed data to find the places where people most often lose their phones.