Unless you're from the UK and of a certain age you've probably never heard of him ... but Andi Peters at the Andaz in LA is my only celebrity sighting. My partner and I grew up watching him present childrens TV every day so it was wierd to sit a next to him at breakfast for a few days.
My only other celebrity 'encounter' was when checking into a Marriot in Zurich. Toni Braxton was staying there and a member of her entourage was shouting at the front desk staff about the lack of variety of fruit in the fruit salad she had ordered.