George W Bush's convoy drove past me in Paris, where he was for an official visit.
It was on a quite deserted avenue, and he was waving at the hysterical crowd (basically me and my dog who was probably having a poo whilst I was foraging in my pocket for a poo bag)
I saw Tim Roth and his lovely wife having a nice parisian dinner on la Place des Vosges. My then boyfriend was talking to me and I was like "ok sounds amazing but we just walked past Tim Roth so you'd have to repeat what you just said because I wasn't listening".
At a Nick Cave's gig, I turned around and saw Mr Bobby Gillespie, to whom my friend (a journo) said hi, I was hysterical (for real this time) and had to let him know that I'm a huge fan, I'm sure he never heard it before.
Was in the same hotel as Ben Folds and his band in Belgium, we had drinks, the bass player even called my bedroom afterwards and sent me messages on myspace (showing my age here) to say that him and his wife were getting a divorce (ok, I guess)
Very recently, Max Minghella and Elle Fanning around London Bridge. They both look fantastic, but him a bit more.
I also saw and interacted with several french somewhat-famous people who are most likely only somewhat-famous in France.