What are some fun things to do in Paris in January?

Can someone tell me what are some good things (the best actually) to do in Paris in mid-January?
Me & 2 friends (middle aged) are going in January and we want to make sure we see all the best Paris has to offer in just a few days.

What's the cheapest and easiest way to call home (US) from abroad (Europe)?

I’m studying abroad for 2 months in Madrid, Spain this summer. I’m also staying a few days in London, England and Paris, France. My family is in southern California and my friends in northern California. What’s the cheapest way to stay in touch with them without them being charged?
If I get a sim card should/can I get a prepaid phone to work with it? I don’t know much of anything about sim and calling cards, do they work like that?

*Note: I can’t use Skype because I’m not bringing a laptop and Skype Mobile for my verizon droid doesn’t work on wifi =(

What are the best tourist sites and activities in paris?

Im going to paris in a few days and staying with relatives for 2 weeks, and i was wondering if there are any great places to go to, or things to do there that you think is worth mentioning besides the laready popular stuff such as the eiffel tower.

What is there to do at the Paris Hotel for a 17 year old?

I’m going to be staying at the Paris Hotel in LAs Vegas for a few days in August and want to know what I can possibly do :]

What to do with kids in Paris for Christmas?

I will be in Paris with three children (1, 2, and 4) for a few days over the Christmas holiday, including Christmas (Dec. 18-Dec 26).

The typical sites aren’t going to be kid-worthy at their age, plus I’ve already seen them, so I’m at a loss for what to do so they won’t be bored and want them to be engaged instead of sitting in a hotel room.

Please advise!
Cabal, awesome! Thank you.

More ideas, please!