Here's a selection I've done for all sorts of clients. Some of these are only propositions, other have been (and are still being) used.

What I generally look for when designing a logo is something clean, easy to read, and without any fuss. There are times when something completely over the top is the perfect solution, of course, but as a rule of thumb I like to keep it as simple and classy as possible, all while keeping every logo unique in its own right.