Who is doing a stellar job of harnessing the power of their client base?

19114332 I gave a presentation on branding in Marco Island, FL (not a bad gig in January) and have since struck up an e-mail conversation with a gentleman from the UK who was there.

He asked me a question that I’m not sure I know the answer to….so I thought I would ask you.  I am confident that you’ll know.

Do "we" know of some other B-to-B companies who are doing a stellar job of marketing to their existing client base to generate additional projects/revenue (in other words…turning clients into a referral source)?

What say you?  Do you have some examples of work you’ve done for a client?  Case studies you’ve read?  Other blog posts you could point us to?  Something you are doing inside your own company?