Yes and No
I always buy the extended warranty for products such as cameras, TVs, game systems, big items like these. If you buy a warranty from Best Buy and something goes wrong they usually replace it from the store's inventory on the spot. Whenever I buy from Best Buy I always buy one of their warranties. I bought my laptop two years ago and from the first day I bought it gave me trouble. After two months of having it the hard drive crashed and the manufacturer had to replace it. Then I continued to have problems with programs shutting down and the system getting over heated. I brought it in Three time for the same problems and just when they were about to replace it at the end of the manufacturer's warranty they told me that they could not duplicate the problem. Funny because I can duplicate it about ten times a day. Anyway the warranties transferred over to the store that I bought it from and they tried working on it. After not having my computer for about 6 months out of the 2 years that I have had it because of being in the shop, it is still not fixed.
In conclusion, warranties are worth it for big items because some companies do stand by their products and repair them. On the other hand some companies screw around with your product (and wipe out your entire system every time you send it in for repair). Thanks a lot HP. Thanks for listening to me let off steam.