I am currently searching for a job, and my mother spotted your job posting and suggested that I email you.
At my last job I was frequently a cashier, and received several compliments on my quick and cheerful service. I have great people skills, am very flexible, and learn quickly. I ... really hate writing cover letters, because it means I'm blowing my own horn very loudly, and I hate that, but there it is. I don't know what else to say.
I have attached my resume as a PDF file.
I look forward to hearing back from you.