I walked to my car to put some things into the boot. Next thing I know I've slammed the boot shut and in the same split second realized that I've locked my keys into the boot.
Walked up to the Langham Hotel and explained my predicament. After some googling and phone calling, I finally managed to get hold of the roadside assist service, who promptly sent someone down in about 3 minutes.
Another 3 minutes later my boot was open and my keys retrieved. Free - or rather, my insurance paid for it.
1. I can be quite an idiot sometimes.
2. Roadside Assist insurance is a must must!