Apart from what Matt said :

2 or 3 years ago I solved a huge problem with a space project for a customer, and I was the hero of the day. The senior engineer told me to have a night out in Cannes, no expenses spared and he'd take care of the bill.

That night I had 2 glasses of cognac that had been on a vat for 75 years. it cost 75 euros per glass or something like that. It was the best stuff I ever tasted. I cannot describe it as anything else than divine (and I am an experienced cognac / whisky taster).

I'd say a couple of hideously expensive bottles of Cognac and Whisky like that the the only luxury item I can think off. (i.e. things that only cost money, and are purely for enjoyment)

And a rotation of razors made by the usual suspects , forged from pattern welded steel, meteorite, wootz, japanese tamahagane...