I'm going on one of those budget college euro package tours at the end of this month. My itinerary looks like this.

Dec 29 - Jan 3: Amsterdam
Jan 3 - 4: Paris
Jan 4 - 5: London

I have an allotted five days in Amsterdam, while only two days in the other two cities (go figure). There are little sightseeing activities planned for three of those days, which means the other two days are completely free. Are there any recommendations for how to use this time wisely and not be a n00b tourist?

I won't have nearly as much free exploration time in Paris or London, but any recommendations (other than the Louvre and the Tower of London) are very much appreciated.

Also, I was wondering if there were any gaming events/public LAN parties going on at that time. I'll have my laptop with me, which has SC and AoE, plus it'd be awesome to meet some fellow ESR locals.