Use the Personal Investment Decision Technique as your litmus test for determining which are the very best companies to interview with on campus (and off). If you would not consider investing in the company from a financial standpoint, they probably should not be at the top of your list of companies with which to interview. Conversely, those companies that are good investments will likely be good employers. Smaller companies may be less noticeable—with far less competition for available jobs.
Please note that this technique does not automatically count out all market giants due to sheer size and already established market domination. Johnson & Johnson, Microsoft, and General Electric are good examples of market leaders who are still at the top of anyone's list of great employers. The key is not size, but whether or not you would be comfortable making a financial investment in the company.
Want some "insider information" in making these decisions? Hook up with a full-service stockbroker. Tell them you are interested in making an investment and that you would appreciate any information they may have on companies x, y, and z. Most are happy to oblige. The annual report is usually the stockholder's prime source of information. Even though it is obviously biased toward the company (after all, they wrote it), it is how they sell themselves as a good investment. You can also use some of the research resources listed in the Employer Research Strategies chapter before you decide whether to interview with the company.
In using this technique, it is important to keep in mind that, as in financial investments, there are always some unknown elements involved. There may be some open questions, but do not wait until you have gathered "perfect information" before making your decision. Gather the information that is available, then make your choices. Do not get caught in the trap of trying to find the "perfect" company. It does not exist. And even if it did, it would not be perfect anymore after you went to work there, right? Instead, seek out a company that is fully committed to growth and excellence, in both the company and its employees.
Again, if you would not favorably consider making a financial investment in the company, then do not consider investing your heart and soul.