There is no better place than the elevator, whether its waiting for the lift or inside. There is a lot of dead time, so why not make some use of it?

It can be anything from as little as "This elevator is always slow" to "What floor are you going? 5? Me too! Do you work in.. blah, blah".

Plus, always be the gentleman (if you are a guy) and let the ladies be the first to walk in or out, and always offer to "push her buttons".