I approach all clerks with a smile and "How are ya now?" and I always try to think of something to say to get a smile out of (most) people. Some clerks that I have become familiar with are most often told a joke I've just heard... never any long jokes because they have jobs to do. Once in a while, even if I am not very familiar with a clerk, say, at a checkout, I'll snicker and say, "I JUST heard this and I gotta tell SOMEone." As well, if the weather is poor but has showed improvement, I work in a quick comment on it as I know what it's like to work 8 hours without a weather update and no windows to see out of.

It doesn't take much and it makes me feel good too.