just like the wireless router you have in your home. You can just take the one from your home, but if you plan on using it for each vacation, it's just easier to by a cheap/small one specific for your travels. I actually have never thought about this before but it's a great idea. DH and I both get on our laptops each night and it can be a pain when we are in a place that only have wired.
That's for the tip!