My primary duty at the public library where I work is adult outreach -- I provide readers advisory services and deliver library materials to homebound adults and residents of various retirement, assisted living, and nursing facilities. In addition to the activities surrounding that work, I also periodicaly work at our general reference and local history reference desks.
I really enjoy working the reference desks. Sure, some days are more challenging than others and some patrons are more challenging than others. But what I love are the fun questions -- the phone call from a lady asking me about beschemel sauce, polenta and hericort vert. And how to pronounce "that word that means fiscal cliff? The one they use on C-span and in the Huffington Post?" (for the record: the word is sequestration). I also live being able to help people do simple things like post an add for a car on craigslist. A car that "runs like a sewing machine, with a booming sound system and good tires."
Not every reference interaction is positive, so it's nice to notice the ones that are.