What if one combines two existing technologies in a new way. For instance combining a word processing program with features from a web site analytics program? Both ideas already exist but the combination is something new. How does this work in general?
In accordance with 35 U.S.C. 103(a), if the combination of the known elements as a whole is something that is obvious to a person with ordinary skill in the art, at the time the invention/combination was made, then the invention is not patentable. Combining a word processing program with features from a web site analytics program may be considered obvious, if there is a suggestion or teaching in the prior art (may be a single prior art or a combination of prior arts) that may motivate one with ordinary skill in the art to combine the elements already existing/known in the prior art. If the combination is obvious to one with ordinary skill in the art at the time the combination was made and if each element in combination merely would perform the same function as it did separately and whether such combination of previously known elements yields a predictable result is something that has to be considered by an Examiner while determining obviousness. If all of the above points are satisfied, then an invention is considered obvious and thus non patentable. If the way you have combined the known elements is something that involves inventive step and if the outcome of such a combination is not obvious to one with ordinary skill in the art given the teachings of the prior art, then your invention may be considered patentable. Obviousness, however, is determined by several other factors. For details, you may visit the links provided below:
http://www.invntree.com/blogs/determination-obviousnessinventive-step-european-patent-office http://www.invntree.com/blogs/determination-obviousnessinventive-step-indian-approach http://www.invntree.com/blogs/determination-obviousnessinventive-step-united-states-america
Some of the above answers are a bit outdated, though still generally useful. As of the America Invents Act (AIA), effective March 16, 2013, 35 USC 103(a) is deprecated. Also, as of KSR Int'l Co. v. Teleflex, Inc., 550 U.S. 398 (2007) there need be no "teaching, suggestion or motivation", found in the prior art, for a combination of known elements to be found obvious.
Nevertheless, it remains true that an invention may be judged "obvious" in view of a combination of known elements functioning in a predictable way. However, if the combination results in an unpredictable function/structure/benefit, satisfies a long-felt need, or benefits from a certain amount of commercial success, it may be patentable. Also, if the two known elements are combined in a novel manner (e.g., a novel interface between the word processor and analytics), the combination may be patentable. Note, however, that each of the elements combined, if individually patented themselves, may prevent the combination from being practiced without a license.
The pencil and erase combination was ruled not patentable as neither function operated differently when combined. I always thought this overlooked the convenience of the operator and that their hand did not have to leave the paper to correct a mistake. This had nothing to do with whether or not combining the two was obvious as I think the Supreme Court simply said there was nothing new.
The short answer is no, due to 35 USC 103(a).
The longer answer depends on the specifics of the combination. In general, if it would have been beyond the skill of an ordinary programmer to import the features of the web site analytics software into the word processing program without a great deal of experimental effort, then it might be patentable (with respect to the prior art; there may still be 101/112 issues). On the other hand, if the combination functions in an expected way and/or offers unsurprising results, it's probably not patentable.
The very short answer is YES - almost every invention can be viewed as the combination of two or more previously known things. Attaching an eraser to the end of a pencil didn't change the operation of either device. If one combined a radio made water proof for use in the bathroom with a bubble blower that blew bubbles according an audio signal from the radio, you might have something novel and non-obvious.