Money for Nothing by Donald E. Westlake. One of the little things that lets you know that Donald Westlake is really very good at what he does is the way in which each of his books manages to take some familiar sort of scene, and spin some clever little turn of phrase off it that's just perfect:

"We don't walk there," Robbie told him. "It's too far to walk. You're a rich guy, we'll take a cab." [...]

Following in Robbie's wake, Josh said, "Why do I always have to pay for the cab?"

"Because you're a capitalist lackey," Robbie explained.

Josh was sure there was a perfect retort to that remark, but as they walked along, southward instead of northward, he didn't hear himself say it, so he never found out what it was.

This is Westlake dabbling in spy stuff: Josh Redmont gets a check once a month for $1,000 from a mysterious outfit named "United States Agent." A halfhearted attempt to locate them never turned anything up, and the checks always clear, so for seven years he's taken the money, and thought nothing more of it. Until one day, a smiling man sits down next to him, gives him a bank book showing $40,000 in an account in the Caymans, and tells him "You are now active."

It seems Josh has unwittingly been accepting money to be a deep-cover agent for some splinter of the former USSR, and now they've come calling. Of course, he's not a spy, he's an advertising executive with a family to support, and he has to find his way out of a tangled mess of bumbling but deadly ex-Soviet operatives.

It's a pretty lightweight book, more in the vein of Put a Lid On It than any of his classic comic novels, but it's enjoyable enough on its own terms. I read this in one sitting, after the family cleared out on Sunday, and it held my interest all the way through. It's not side-splittingly funny, but there are some good moments, and Westlake still knows how to construct a plot.