Taboo is one of my favorite board games. It can accomodate either a large group of people or just a few of your close friends (from 6-14). The rules are simple so it's easy to learn. You are granted a card with a word written at the top of the card, followed by a list of related words below it. You are to try and get your teammates to guess this word without using the accompanying set of words. For example, to describe water, the card may tell you that you cannot use "drink, fluid, wash, rinse" etc. the idea is simple, but the game is NOT easy. Gesturing and drawing are also not allowed.
Taboo does not get boring. I've played it many times with family and friends and it is fun everytime. You do not have to worry about running out of words to say or memorizing it, because you can always purchase new card packs from game stores. It really tests your ability to act quickly under pressure - a whole other aspect of a person's intellect that an IQ test cannot define. You may find some of your smarter friends stumped due to the nerveracking sight of the sand escaping the top half of the hourglass.
Overall it is a intelligent but simple game that will get your friends together for 1-2 hours of wholesome fun. You might even incorporate your own rules, for example loser takes a shot of alcohol :P. Loser keeps on losing and winners get to laugh at the losers. good times.