I had already made my donation when I read Lunk's post, but thought he made an interesting point. So, I am having a three week break from Cafe Nero next door to the office. I'll make coffee on-site instead.

That will save me £2.15 per day, times 15 days = £32.25
With current exchange rates, that is about $63.33 (I'll round to $65)

PayPal'ing it over now... (and trying not to fall off chair with shock after realisation of how much £ I waste on take-away coffee!)