I use a pendulum. It was actually my first form of divination. Yes, I know that they are easily manipulated physically, but with the proper grip, it is hard to do without being obvious. The problem that I have found is that they are hard to use for yourself because they are also easily manipulated mentally. The pendulum works by reading your own vibrations. Therefore, if you want a certain answer, that is probably the answer that you will get because that is what is in your head. On the other hand, I have found that I am very accurate when using it in readings for others. I even had one that would spell answers to questions that were not yes or no. My friend and teacher, a Native American Shaman and Druid Crone (yes I know it IS an interesting mix) taught me how to use my pendulum and make different charts. (Alphabet, numbers, direction, probabilities, etc.) Gemini was right, if you are impartial or do not conciously know the answer, the more accurate you will be. The last time I "played" with it with a friend and non-believer, I had about a 90% accuracy rate. He asked me yes or no questions that I could not possibly know the answer to. Did I have milk with my dinner, did I leave work early last week, was I late this morning, etc. He went from non-believer to totally freaked out real quick. Luckily, if I want a pendulum reading, I have several friends who are very adept with theirs and we swap readings on a pretty regular basis.
I have also found that my pendulum and an alphabet chart are a great way to channel my guides. You have to be very careful when doing this because you may also channel things that you do not want to channel. I recommend a circle or at the very least a cleansing chant and a prayer of intent.
I hope you can understand all of this, I do tend to ramble. It's a good thing I'm cute or I would never get away with it! }>