I've been doing a lot of research on advertising agencies, marketing companies and consulting firms in the US and UK, for the past couple of months and must have gone to over 1,000 sites. Its been a really fun experience and I have thoroughly enjoyed the creative aspect of it. While some agencies have a bare bones listing of facts about themselves, other go overboard on the creative angle and bombard you with flash.
One of the good sites is MindComet, an Interactive Agency with headquarters in Orlando, Florida and offices in Los Angeles, New York, Atlanta and Austin. I think the MindComet site has the right mix of information (about the company), attraction (to what they do and how your company could use their solutions) and creativeness (graphics and pics).